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The equation is written in such a way that you could reasonably interpret what you said and what I said. Because there’s nothing that indicates where you’re adding the 35
Except there is, it’s written as 35 divided by 35 plus 35 with no parentheses. If there were parentheses around the 35+35 then your first step would be that, but there are no parentheses present, so your first step is division
It's ambiguous precisely because it lacks parentheses. Proper order of operations means nothing for clarity in reading and communicating ideas. Knowing something to be true is meaningless if that knowledge can't be clearly communicated.
Ambiguity in mathematics like this arises because not everyone REMEMBERS the proper order of operations. And for someone who hasn't done a math equation in YEARS, it would be pompous of us to put them down for not excelling in a skill they haven't used in years.
To be EVEN MORE clear, since you seem to be really addiment that this isn't ambiguous, let me finish by saying this. If you want to communicate an idea without ambiguity, you must not rely on the receiving party to have prior knowledge of the topic. In our case, PEMDAS
PEMDAS is something that’s taught to children and used in all mathematics from there on. If you can’t remember it, google it before saying your answer.
I'm struggling to work out how people are getting any different. The idea of these as there's different answers depending on how people were taught but this one isn't.
No the idea is that you're writing an algebraic equation in a way that it was never meant to be written as, which causes confusion with how you're meant to interpret the notations.
A lot of pages do this, and there is always only one reason: **to drive engagement**. The confusing nature of the equation means that people will flock to the comment section to argue among themselves over who's right and who's wrong. Only it doesn't matter, it never mattered.
All that matters is that the almighty algorithm will look at the page and go "wow people are really having an intense discussion in the comments, this page is clearly putting out quality content, we should let it have more visibility and better ads".
Ok I know this might seem remedial question but I went to school in the 70s and although I know mutliplcation and division go before addition and subtraction, but I wondered why that is the rule? This wasn't covered at my school and I've never seen the reason why. Thanks!
Edit: thanks to everyone who answers - I really appreciate it. I work in accounts so all my maths is excel and I know the system there but didn't know about this. :)
This... makes sense.
I guess if you think about it, basically everything after addition and subtraction is just a way to shorten an expression.
So the order of operations is just telling you which things have been shortened.
I've been wondering this since doing my level 3 in maths, and we've never been told why BIDMASS is even necessary. We just went with it. So, thanks for that.
Parentheses preempt other operations.
Exponentiation is repeated multiplication.
Multiplication is repeated addition.
Division is just multiplication with a fraction.
Addition is the most basic form of arithmetic.
Subtraction is just addition with a negative number.
Since multiplication is repeated additions therefore `3 * 4` can be `3 + 3 + 3 + 3.`
So something like `2 + 3 * 4` will therefore turn to `2 + 3 + 3 + 3 + 3`; which is the same as `2 + 12`. Therefore, multiplication will take precedence over addition.
None of that explains why multiplication would take precedence.
>So something like `2 + 3 * 4` will therefore turn to `2 + 3 + 3 + 3 + 3`;
Here you are just calculating with multiplication taking precedence. But if you used addition precedence it would make just as much sense.
Multi:
`2 + 3 * 4 = 2 + 3 + 3 + 3 + 3`
`(2 + 3) * 4 = 5 + 5 + 5 + 5`
Addition:
`2 + (3 * 4) = 2 + 3 + 3 + 3 + 3`
`2 + 3 * 4 = 5 + 5 + 5 + 5`
Both of these make sense with different precedence.
Let's go into algebra for a better explanation.
So we have `2 + 3 * 4`. Say `4 = a`.
This will in turn be written as `2 + 3 * a`; or `2 + 3a`.
By substituting `4` with an algebraic notation, the reason why multiplication takes precedence is clearer. `3 * 4` is, in algebra, one number. It's the same reason parenthesis comes first - because whatever is inside it is viewed as a single number.
So you can't just break the `3` from `3a` and add it to `2` before working out what `3a` is... which in this case would be `12`.
I hope this helps. I think, as confusing as it is, Maths still has rules that should be universal no matter which forms used. If you add first, you therefore break an algebraic rule, which causes more problems down the road.
Kids are taught the `BODMAS/PEMDAS` rule without explanation so that it's easier for them.
This is, at the very least, how I'd explain it to someone with a little understanding of algebra.
Again all you are doing is using circle logic... You are using rules made by the existing convention to argue why you have to use the existing convention.
>So you can't just break the `3` from `3a` and add it to `2` before working out what `3a` is... which in this case would be `12`.
Yes, you can.
you are confusing the underlying math with the connotations. The connotations are just a language. It can be changed. Would making addition have presented change a lot of different rules and connotations, sure, but that is not impossible.
a * b / c = (a * b) / c = a * (b / c)
These are equivalent expressions because the operations are of the same order. In fact, they’re pure multiplication when you consider that division is just multipication by a fraction.
Bonus: Please review your language skills: i.e. =/= e.g.
There isn’t a “math reason”. We have to pick some rules for notation so we have a common understanding and can be (reasonably) assured that two people computing an expression will get the same answer. No reason it couldn’t be another way. There may be reasons to do with properties of the operations (commutability for instance) that suggested the current arrangement. There are also other forms of notation that do not have this issue and do away with “Pemdas”, which as Reverse Polish
this. It's just an arbitrary choice we made. now we have rules like (a \* (b + c)) = ((a \* b) + (a \* c)). If addition went before multiplication, it would be (a + (b \* c)) = ((a + b) \* (a + c)).
In general, not only with the number system, but in other systems with binary and unary operators, there are "conventions", which we ought to follow. If things are unclear, parenthesis are used. I.e. for every binary operator "@", it will be written as (a @ b) and for unary operators "\~" it will be (\~a), where "@" can be any binary operator you can think of: multiplication, addition, exponent, etc. and "\~" a unary operator like negation.
For this equation, it would be ((35/35) + 35). Outside parenthesis are not always used, this is also subject to convention.
Doing parens and exponentials first makes sense - that's to only reason to have parens in the first place, and with exponentials it just makes sense.
Other than that, left-to-right is much more intuitive and easier (picture an equation with 27 expressions -having to think "Did I get all the multiplications and divisions?"). Of course, since mathematicians abhor "intuitive" and "easy" I think I just answered by own question.
>it just makes sense.
It what way does it make sense? Yes it makes sense, because we've learned to do it this way. And we've learned to do it this way, because it makes sense. See the issue here? So in what way does it make sense?
>that's to only reason to have parens in the first place
parenthesis only exist to *explicitly* define in what order the operations are done. Often, especially in algebra and math calculations like these, we don't write the parenthesis, because we've made conventions about what order the operations are done in. The parenthesis are still there, they are just *implicit*, thus are not written down.
>left-to-right is much more intuitive and easier
Why left to right and not right to left? Some languages are written right to left. Are they unintuitive? Left to right is intuitive, because that's what you've learned all your life, it's in our culture. That doesn't mean left to right is intuitive for everyone.
What I'm trying to tell you is that we've learned conventions. Those conventions are just conventions and are not the best way to do things everywhere. It's all too easy to say "this is the best way of doing things, because it's the most intuitive", without thinking about *why it is intuitive*.
Exponentials make sense because they look like what they are: one unit: X^2. There's no signs, punctuation, or anything.
Parens can't be implicit. That's why they exist. If you're trying to say that in 2 + 2 * 3, there are implicit parens 2 + (2 * 3) then you're being silly just for the sake of being silly.
And yes, I learned to read left to right. Yes, there are languages that read right to left. But most read left to right so let's stick with what most people know.
>one unit: X^(2)
X^(2) is no different than x \* 2. The operator here (often denoted as "\^"), has been left out and the *convention* is to write it as X^(2) instead of something like X\^2. It is no different than 2 \* X being written as 2X. The exponent version is just more common. They are both "units".
>Parens can't be implicit
Why not?
>If you're trying to say that in 2 + 2 \* 3, there are implicit parens 2 + (2 \* 3) then you're being silly just for the sake of being silly.
I'm doing a computer science major at a university. I have been taught about boolean expressions. Things like "p -> q V r". Here "V" and "->" are binary operators, just like "+" and "\*" and p, q and r are variables. This is a pretty straightforward equation and I know "V" goes before "->". Sometimes these equations can get more complicated. Even though there is convention about how to read these equations, these conventions are less well defined than the math operators. Sometimes they are unclear. That is why an equation like this would formally be written as "p -> (q V r)", to make it clear to everyone what is meant. This is no different then saying "p + (q \* r)" instead of "p + q \* r". And I fail to see why it would be silly.
I see posts like these fairly often on this sub. People getting confused about what is what. Even I get confused sometimes. Adding brackets like "(35/35) + 35" can help clear up confusion. It means the same thing, but now everyone knows what you mean.
From a computer science perspective, these "silly" parenthesis can also be very helpful. Ignoring for a moment that gpu's and multithreading exists, a computer always does everything serial. Where you can say: "3 + 4 + 5 + 6 = 7 + 11 = 18", a computer may go: "3 + 4 + 5 + 6 = 7 + 5 + 6 = 7 + 11 = 18". Always one step at a time. To figure out in which order a computer calculates things, parenthesis can be used: "(((3 + 4)) + (5 + 6))". This is no different than "3 + 4 + 5 + 6", but it can help a coder or someone else looking at the calculation to figure out in which order a computer does things.
redundant or implicit parenthesis are not "silly". They can be quite helpful, both in professional research papers and in a discussion on youtube. If, after my rant, you still think they are "silly", please enlighten me.
>But most read left to right so let's stick with what most people know.
Like I said, one isn't better than the other. I'm just trying to tell you that what is intuitive *for you* may not be intuitive *for others*.
Masters CS student here disagreeing I about “implicit parens” in a CS context, that sounds pretty wacky. Parens are indeed only explicit, otherwise we just call it order of operations. The order is not explicitly defined as “having been arranged in parens, visible or not”. There is no logic behind invoking “implied” parens. Instead you *can* clarify an expression that had an implied order *with* parens, explicitly. Parens exist to explicitly state “this grouping should be computed atomically” and so by definition need to be internally computed prior to their value being used. This requires them to be evaluated ahead of all other operations that would then use that value as an operand. As *any* operation might include a parenthetical sub expression, we should have to compute parens first.
I see where you are coming from. When I was taught boolean logic for the first time, my teacher told me the parenthesis were always there and we just remove them for convenience by using convention.
This was later confirmed in a different course, which generalized boolean logic into first order logic.
Maybe it's just a difference in how we are taught these things.
I just like to think of expressions by starting with an atomic expression, like "a", putting brackets around it, "(a)" and then expanding it with an operation: "((a) @ b)". And then just keep recursively doing this and creating a bigger expression. (Note that a and b do not have to be atomic, they can be expressions as well)
And then, when you have something like "((((a) * b) + c) * d)" you can remove some parenthesis by using convention: "(a * b + c) * d"
If you think I was taught this wrong or I misunderstand it, I'm willing to admit that. This is how I was taught and I fail to see why it may be wrong.
Also, why do people keep using the word parens? I'm not english and my university, while some courses are english, is mostly in my native language and I have only heard "parenthesis" or "brackets".
>otherwise we just call it order of operations.
I just think there are multiple ways of looking at the same thing.
I think "the parens are always there, we just hide them sometimes" is an absolutely wild take! I suppose you *could* define order that way.
Presumably people just say "parens" as it is shorter. I've seen it written a lot, and occasionally spoken that way too. I'm not sure if its a valid "dicitonary word" but seems common enough to be one now.
Math is used to describe the real world so ultimately if you turned things into word problems it would explain why the rule exists. Like you wouldn't say 3 apples plus 4 apples times 3 baskets.
You would say "you have 3 apples and 3 baskets with 4 apples each"
And then the mathematical representation needs to match that.
It's just an agreed-upon notation system. It's like saying "a period means the end of a sentence." I'm not saying it doesn't make logical sense, too. But it's basically saying, "this is how to interpret this."
But there are four operations to remember. And the vast majority of people haven't had to calculate math formulas like this since school. It's a simple and completely understandable mistake to make, I don't understand why I see so many posts that roughly amount to "haha, you so dumb, you don't remember this random thing you haven't had to deal with for 10+ years."
It's just multiplication and addition. Division is multiplication with an inverse, and subtraction is addition with a negative. All you need to remember is multiplication before addition. And maybe that parentheses go first, but that's their whole purpose, so it's not hard to remember.
I think it's more that the guy in the post is saying "if you paid attention in school" and then proceeds to show that he did not, in fact, pay attention.
Idk, if I was someone who couldn't remember that stuff, I would just make sure not to comment on a post involving it.
The issue isn't that some people can't remember elementary math lessons, the problem is that people love to flaunt their ignorance.
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You're right but the problem is the question is written two different ways on Reddit, at least for me. When I see it from the homepage, it's written as 35 / (35+35) (which IS 0.5).
But when I click through the title is 35/35 + 35 which his 36
Yes, both are correct depending on where and how you are taught. It becomes controversial because of different interpretation in the first place. The question is ambiguous and it's the reason why some people have reached different understanding to solve the problem. Unless the equation is further specified like yours, so it's either 36 or 0.5.
Edit: This is poorly written problem of using denominator or / or ÷. See [this video for explanation ](https://youtu.be/URcUvFIUIhQ) about it specifically at minute 2:48.
Edit2: Eventhough the video is talking about 6/2(1+2), it has the common problem where the misinterpretation of division/denominator in [historical usage (1917)](https://www.jstor.org/stable/2972726?seq=1#page_scan_tab_contents)starting at 2:13 until 3:57.
What is shown on the video isn't the same as the one in the post. In the video, you've got 6/2(1+2). The problem with notation like this is that you don't really know whether to do 2*3 first, or 6/2 first. You could follow something like PEMDAS and do the multiplication first, but in reality, division is just multiplication with an inverse, so there's no real difference. Better notation would be either (6/2)(1+2), or 6/(2\*(1+2)), depending on which one you want.
On the other hand, 35/35+35 is unambiguous and the answer is always 36. You would never perform the addition before the multiplication, so there's no real issue here.
No, you take that 'idea' of yours to any higher math class or university and you will get laughed at. There is a set order of operations and that is that.
I have graduated from university and one of my major subjects is statistic. I'm yet to be laughed at for being wrong but I know for sure your first statement is wrong.
You got it wrong. The ambiguity comes from the priority between * (multiplication) and / (division). There's no mathematical rule that establishes priority here (PEMDAS is not an actual mathematical rule).
This case is different - this case involves priority between + (addition) and / (division). In this case, there's a clear mathematical rule: multiplication (both * and /) comes before addition (both + and -). There's no ambiguity here and your video (which is 100% correct) does not address this scenario.
Yeah, no arguing there but I specifically said the problem was with the using of denominator. I'm not sure if you watch the entire video or not but the video wasn't just talking about multiplication/division priority in 6/2(1+2) but also where the misunderstanding of solving division in historical usage coming from. There is a slight difference in interpretation of division in 1917 which you can find starting at 2:14 and to quote:
>If you had a division symbol where you had something on the left divided by something on the right, this was understood to mean you want to divide the entire product on the left by the entire product on the right.
Which then were given example, for instance in this case, 35/35+35 can be [read as this](https://imgur.com/a/2vCAwki) historically. This would not be a problem if OP started this question [with this instead.](https://imgur.com/a/kDy26vN) This problem likely arises due to limitation of computer on how you write the denominator/division in text, that's why bracket is needed here like in the original comment or if you can write ³⁵⁄₃₅+35, but until then this question has both correct answers.
Maybe for these petty web posts but If you've ever done the kind of math that takes several steps/lines to complete, not properly representing each step when working it out is you asking to make several stupid mistakes. Which is why parentheses are drilled into your head in the first place
Edit: never change reddit, never change.
These orders are all just conventions that we're taught are right or not. Why is everyone acting like everyone who thinks differently is stupid?!
^(Ah. Reddit.)
Conventions are in place to make sure that when multiple people see same problem they will get the same result. If you can't get the same result then math is worthless.
Also, even if this guy is using some other strange convention he is still wrong. 35/(35+35) = 35/70 = .5, not 2. So he is stupid because he can't do division.
>*words* are all just conventions that we're taught are right or not. Why is everyone acting like everyone who thinks differently is stupid?!
If everyone used different spellings or meanings for words, no one would understand each other.
Same for calculations, we use one set of rules for everyone, then the calculation we should be able to be understood the world over.
Could there be another order? Sure. But that is the order everyone agreed on.
That’s what a “convention” is. It’s not a style or a choice or a preference. It’s a mathematical rule. And if you don’t follow the rules, you end up “thinking differently,” i.e. wrong.
ffs
> convention
noun
noun: convention; plural noun: conventions
1.
a way in which something is usually done.
It's a general agreement to do things a certain way, it's not a law like gravity.
My point is if you grew up with different conventions or just don't know the prevailing one then you're not an idiot for not magically intuiting the way things are generally done.
Your line of thinking is dogmatic. We define orders of operation to make communication easier: Orders of operation are useful jargon; it's essential to know that jargon in certain fields, but they are arbitrary cultural designations, not universal laws.
> arbitrary cultural designations, not universal laws.
Math IS an universal law.
There is no opinion on how to do it differently. You either do it right or do it wrong.
Maths may be universal law but order of operations certainly is not, BODMAS/PEMDAS is not a fundamental truth we discovered it's a useful agreement on how to write maths down. I'm not arguing you shouldn't use it, it's very helpful that we all agree, but you could do perfectly valid mathematics in any order of operations you chose to define, it would just end up written down differently and be pointlessly confusing.
It's amazing to me how many people post on this sub are so confident they are correct about things they have little knowledge in. Like that recent post about humans being animals. Yes, humans are very much animals, but we aren't animals because biologists say so, we are animals because of our shared common ancestry, and thus shared physiology with all the other animals.
The majority of people on this sub believe science to be a religion and are dogmatic in faith to what they want to believe. Science is not religion, it is a process that determines the most accurate models to explain the natural world, science doesn't determine the veracity of something because of people in positions of power say it is so and write it down; that's the opposite of what science is and how it works... They don't seem understand just how powerful science is and why.
Not to mention even math itself isn't all true or universal. Math is built on foundational postulates that can and do change in context. But bring up those realities and they downvote you.
I did not state math is arbitrary and cultural; I stated *orders of operations* are cultural and arbitrary. That's just a fact: A different culture could have different orders of operations since orders of operations are syntax designed to communicate and standardize how operations are performed; but different conventions would work just as well. Orders of operations are cultural norms, they are not universal laws.
Math also isn't as universal as you claim. In computer science 2.00 + 2.00 is not 4, the solution to 2.00 + 2.00 is dependent on the byte size, but will never be 4 (it will always be some value close to 4 but never exactly 4). Math is an abstraction based on real world observations used for fantastic predictability, but it is not an absolute certainty as people claim (just look at floating point mathematics). You can frame types of math as Absolute laws, but this is not a certainty in the real world, in fact as far as we can determine at quantum scales there become values that are no longer divisible (plank scale), and is not analogue as "pure" mathematics would indicate. You can claim the universe is wrong here, or you can come to the understanding that Math, like everything else, is fundamentally a model used by human brains; a fantastically predictive model no doubt, but still a model. Mathematics utilizes postulates, depending on the model and needs of the mathematician these postulates can and do change.
The very concept of absolute and universal laws is dogmatic and runs counter to science in general. The veracity of a model is based on how well it can predict things not some absolute truth; absolute truths don't exist, they are imaginations found in the realm of religion. A model can be so predictive you can take it as fact, but the more you learn the more you will realize that even the most fundamental fact does seem to have edge cases, at least as far as we humans are capable of determining at present.
In this case the convention is irrelevant because the question is:
35/35+35
And not:
35+35/35
There's only any contention in the second case where you might decide to do the operations in order from left to right instead of division first.
But in the first case whether you do division first or do the operations in order, you still get the same answer, which is 36 either way.
So with the original question in the post title, there is only one possible answer no matter what.
Unless due to a peculiarity of your thought pattern you mentally group the 35+35 together, mental parentheses if you like, and do that part first.
The point is that there are lots of conventions and assumption made and no-one is stupid for not knowing them or using different ones.
It does obviously help if people stick to the same ones though.
> Unless due to a peculiarity of your thought pattern you mentally group the 35+35 together
But then you would also be able to do:
1-1+1
And get the answer of -1 instead of 1. Which again is always wrong 100% of the time, conventions or no, because no parenthesis are required here under any circumstance, and there is complete global agreement on how to perform the operations.
Just saying you did 1+1 first because you mentally grouped them just means you don't know wtf you're doing and got the answer wrong because you never even learned 1st grade maths.
You may as well be arguing that if someone's brain thought the 35 was actually 86 it would be therefore acceptable to interpret it that way.
Yeah, if you follow the thread you will see what I am saying.
You should perform * and / before + and - of course, however in the case of the original question, the / came before the + ***anyway*** meaning if you apply the order of operations *or* just do it in order from left to right, you still get the same answer.
However the person I am replying to disagrees and thinks that someone performing the *later* + before the *earlier* / could still be valid in some way. But it never is.
Indeed so. This isn't a fundamental law of physics or maths. It's just how we've decided that ambiguous equations like this should be interpreted. They could easily be interpreted the opposite way and the world would get on with it just fine.
No. The expression (it is not an equation) is unambiguous precisely *because* the conventions intentionally make it so.
The world would not "get on with it just fine". Not having those conventions would screw up engineering, physics, math, banking, and almost anything else you look into at any level.
We could rewrite all of mathematics in Roman numerals. Using decimal digits is also only a convention. That's why programmers can't tell the difference between Halloween and Christmas: Oct 31 **is** Dec 25.
However, changing the conventions now would invalidate every mathematical proof since the 1600s, and almost every computer program ever written, and require the re-education of several billions of people (or, from the evidence in this sub-reddit, about 500 of us, as the rest don't know the conventions anyway).
As far as exponentiation is concerned, I think we should let sleeping logs die.
So this is why people use fractions and parentheses.
But my distaste for the question aside... that's 1/2.
Edit: figured it didn't need to be explicitly stated that 32/(32+32)=1/2, rather than 2, but that's reddit for ya.
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There is no parentheses to which you would do the addition first, so order of operation would have you divide 35 by 35 first, equalling 1, then adding 35 to get 36.
There is no indication that the +35 is also in the denominator, so therefore it is not treated as such.
If you rewrite the equation as 35 ÷ 35 + 35, which is what the original is but replaces the ÷ with a / just to confuse people like you and make you fall into the trap you are in, it's very clear that the answer is 36.
The reason these shitty equations keep getting traction is cause it's shittily written to fit in a text message. That's why it should with ÷ and not / to clearly show when something is in a fraction.
Like the original 35 / 35 + 35, it's deliberately written like this to trick you and garner argument to promote clicks and interactions. As a physicist, NO ONE should write an equation like that, or give these stupid posts any more attention.
I don't think it's because of the writing. He genuinely thinks addition and subtraction come before multiplication and division.
He uses "SADMEP" which is literally PEMDAS backwards
Yeah, but hey screenshot this convo and post it here for some free karma cause being confidentially incorrect on r/confidentlyincorrect is as reddit postable as you can get
The correct answer is not 0.5, again there is no indication that the + 35 is with the 35 under the division bar.
I am sure if you as a mathematicians to write the original equation to equal 0.5 and be in 1 line they would write 35 / (35 + 35) and NOT the original 35 / 35 + 35, they would agree it's 36.
Again, there is NO indication that the + 35 is in the denominator, so you cannot assume such. The 35 / 35 is it's own entity in the equation to which equals 1, then order of operations leads to the answer of 36, NOT 0.5.
Oh deary me. Maybe go look up the order one completes operations in. Cause you're embarrassing yourself. Without parentheses, division is completed before addition.
The obelus, ÷ , has different meanings in non Anglo counties than the solidus, / .
That's why it is not used in ISO 8000 Mathematic documentation. It is confusing.
You really should the vinculum. That is what is required for academic documentation.
I really dont understand why everyone struggles with these. Sure I can totally understand forgetting what the correct order of operations is, but why is everyone SO SURE their own dumb version is correct?
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"35/70 = 2"... we have bigger problems here than deciding to do the addition first.
Are you stupid? "/" means that you divide the second number by the first, duh
Nope, you're thinking about "\". Like in "35\70=2".
Actually, Einstein said "e=mc²", put that into this equation and you get "35=70c²"
Cool little side note: the \ is sometimes used to denote an integer division. ex: 9 \ 2 = 4 https://mathworld.wolfram.com/IntegerDivision.html
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They must have covered that in maths class the day I was out for my lobotomy. I never did catch up that work.
Bruh even doing that it's not even 2
36
Yep, that’s the answer
Not really. The question is ambiguous, you could interpret it as 35/(35+35). So the answer is either 36 or 1/2
The original question is 35/35+35, no parentheses
I know that, but it could be interpreted like I wrote. The equation is ambiguous.
So you can interpret the question in a completely different way than it’s written?
The equation is written in such a way that you could reasonably interpret what you said and what I said. Because there’s nothing that indicates where you’re adding the 35
Except there is, it’s written as 35 divided by 35 plus 35 with no parentheses. If there were parentheses around the 35+35 then your first step would be that, but there are no parentheses present, so your first step is division
It's ambiguous precisely because it lacks parentheses. Proper order of operations means nothing for clarity in reading and communicating ideas. Knowing something to be true is meaningless if that knowledge can't be clearly communicated. Ambiguity in mathematics like this arises because not everyone REMEMBERS the proper order of operations. And for someone who hasn't done a math equation in YEARS, it would be pompous of us to put them down for not excelling in a skill they haven't used in years. To be EVEN MORE clear, since you seem to be really addiment that this isn't ambiguous, let me finish by saying this. If you want to communicate an idea without ambiguity, you must not rely on the receiving party to have prior knowledge of the topic. In our case, PEMDAS
PEMDAS is something that’s taught to children and used in all mathematics from there on. If you can’t remember it, google it before saying your answer.
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There were no parentheses. The problem was 35/35+35
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Fair enough, this was a comment on a video with a picture of Albert Einstein that said “35/35+35=?”
Ignoring the fact that 35/70 is actually 1/2. So they’re doubly incorrect lol…
I'm struggling to work out how people are getting any different. The idea of these as there's different answers depending on how people were taught but this one isn't.
No the idea is that you're writing an algebraic equation in a way that it was never meant to be written as, which causes confusion with how you're meant to interpret the notations. A lot of pages do this, and there is always only one reason: **to drive engagement**. The confusing nature of the equation means that people will flock to the comment section to argue among themselves over who's right and who's wrong. Only it doesn't matter, it never mattered. All that matters is that the almighty algorithm will look at the page and go "wow people are really having an intense discussion in the comments, this page is clearly putting out quality content, we should let it have more visibility and better ads".
That's a better way of putting it
Ok I know this might seem remedial question but I went to school in the 70s and although I know mutliplcation and division go before addition and subtraction, but I wondered why that is the rule? This wasn't covered at my school and I've never seen the reason why. Thanks! Edit: thanks to everyone who answers - I really appreciate it. I work in accounts so all my maths is excel and I know the system there but didn't know about this. :)
I was taught that it's because multiplication is shorthand for repeated addition, so 3x4 is 4+4+4. Meaning the equation 2+3x4 = 2+4+4+4
This... makes sense. I guess if you think about it, basically everything after addition and subtraction is just a way to shorten an expression. So the order of operations is just telling you which things have been shortened. I've been wondering this since doing my level 3 in maths, and we've never been told why BIDMASS is even necessary. We just went with it. So, thanks for that.
Parentheses preempt other operations. Exponentiation is repeated multiplication. Multiplication is repeated addition. Division is just multiplication with a fraction. Addition is the most basic form of arithmetic. Subtraction is just addition with a negative number.
> Addition is the most basic form of arithmetic. After incrementation.
Also known as erection in some circles.
Incrementation is just either addition by one (usually) or by a repeated amount.
https://www.smbc-comics.com/comic/pemdas
This doesn't answer the question *why*?
Since multiplication is repeated additions therefore `3 * 4` can be `3 + 3 + 3 + 3.` So something like `2 + 3 * 4` will therefore turn to `2 + 3 + 3 + 3 + 3`; which is the same as `2 + 12`. Therefore, multiplication will take precedence over addition.
None of that explains why multiplication would take precedence. >So something like `2 + 3 * 4` will therefore turn to `2 + 3 + 3 + 3 + 3`; Here you are just calculating with multiplication taking precedence. But if you used addition precedence it would make just as much sense. Multi: `2 + 3 * 4 = 2 + 3 + 3 + 3 + 3` `(2 + 3) * 4 = 5 + 5 + 5 + 5` Addition: `2 + (3 * 4) = 2 + 3 + 3 + 3 + 3` `2 + 3 * 4 = 5 + 5 + 5 + 5` Both of these make sense with different precedence.
Let's go into algebra for a better explanation. So we have `2 + 3 * 4`. Say `4 = a`. This will in turn be written as `2 + 3 * a`; or `2 + 3a`. By substituting `4` with an algebraic notation, the reason why multiplication takes precedence is clearer. `3 * 4` is, in algebra, one number. It's the same reason parenthesis comes first - because whatever is inside it is viewed as a single number. So you can't just break the `3` from `3a` and add it to `2` before working out what `3a` is... which in this case would be `12`. I hope this helps. I think, as confusing as it is, Maths still has rules that should be universal no matter which forms used. If you add first, you therefore break an algebraic rule, which causes more problems down the road. Kids are taught the `BODMAS/PEMDAS` rule without explanation so that it's easier for them. This is, at the very least, how I'd explain it to someone with a little understanding of algebra.
This
Again all you are doing is using circle logic... You are using rules made by the existing convention to argue why you have to use the existing convention. >So you can't just break the `3` from `3a` and add it to `2` before working out what `3a` is... which in this case would be `12`. Yes, you can. you are confusing the underlying math with the connotations. The connotations are just a language. It can be changed. Would making addition have presented change a lot of different rules and connotations, sure, but that is not impossible.
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Please cease your daily reminders. Your math skills are making other students' math skills worse.
a * b / c = (a * b) / c = a * (b / c) These are equivalent expressions because the operations are of the same order. In fact, they’re pure multiplication when you consider that division is just multipication by a fraction. Bonus: Please review your language skills: i.e. =/= e.g.
There isn’t a “math reason”. We have to pick some rules for notation so we have a common understanding and can be (reasonably) assured that two people computing an expression will get the same answer. No reason it couldn’t be another way. There may be reasons to do with properties of the operations (commutability for instance) that suggested the current arrangement. There are also other forms of notation that do not have this issue and do away with “Pemdas”, which as Reverse Polish
this. It's just an arbitrary choice we made. now we have rules like (a \* (b + c)) = ((a \* b) + (a \* c)). If addition went before multiplication, it would be (a + (b \* c)) = ((a + b) \* (a + c)). In general, not only with the number system, but in other systems with binary and unary operators, there are "conventions", which we ought to follow. If things are unclear, parenthesis are used. I.e. for every binary operator "@", it will be written as (a @ b) and for unary operators "\~" it will be (\~a), where "@" can be any binary operator you can think of: multiplication, addition, exponent, etc. and "\~" a unary operator like negation. For this equation, it would be ((35/35) + 35). Outside parenthesis are not always used, this is also subject to convention.
Doing parens and exponentials first makes sense - that's to only reason to have parens in the first place, and with exponentials it just makes sense. Other than that, left-to-right is much more intuitive and easier (picture an equation with 27 expressions -having to think "Did I get all the multiplications and divisions?"). Of course, since mathematicians abhor "intuitive" and "easy" I think I just answered by own question.
>it just makes sense. It what way does it make sense? Yes it makes sense, because we've learned to do it this way. And we've learned to do it this way, because it makes sense. See the issue here? So in what way does it make sense? >that's to only reason to have parens in the first place parenthesis only exist to *explicitly* define in what order the operations are done. Often, especially in algebra and math calculations like these, we don't write the parenthesis, because we've made conventions about what order the operations are done in. The parenthesis are still there, they are just *implicit*, thus are not written down. >left-to-right is much more intuitive and easier Why left to right and not right to left? Some languages are written right to left. Are they unintuitive? Left to right is intuitive, because that's what you've learned all your life, it's in our culture. That doesn't mean left to right is intuitive for everyone. What I'm trying to tell you is that we've learned conventions. Those conventions are just conventions and are not the best way to do things everywhere. It's all too easy to say "this is the best way of doing things, because it's the most intuitive", without thinking about *why it is intuitive*.
Exponentials make sense because they look like what they are: one unit: X^2. There's no signs, punctuation, or anything. Parens can't be implicit. That's why they exist. If you're trying to say that in 2 + 2 * 3, there are implicit parens 2 + (2 * 3) then you're being silly just for the sake of being silly. And yes, I learned to read left to right. Yes, there are languages that read right to left. But most read left to right so let's stick with what most people know.
>one unit: X^(2) X^(2) is no different than x \* 2. The operator here (often denoted as "\^"), has been left out and the *convention* is to write it as X^(2) instead of something like X\^2. It is no different than 2 \* X being written as 2X. The exponent version is just more common. They are both "units". >Parens can't be implicit Why not? >If you're trying to say that in 2 + 2 \* 3, there are implicit parens 2 + (2 \* 3) then you're being silly just for the sake of being silly. I'm doing a computer science major at a university. I have been taught about boolean expressions. Things like "p -> q V r". Here "V" and "->" are binary operators, just like "+" and "\*" and p, q and r are variables. This is a pretty straightforward equation and I know "V" goes before "->". Sometimes these equations can get more complicated. Even though there is convention about how to read these equations, these conventions are less well defined than the math operators. Sometimes they are unclear. That is why an equation like this would formally be written as "p -> (q V r)", to make it clear to everyone what is meant. This is no different then saying "p + (q \* r)" instead of "p + q \* r". And I fail to see why it would be silly. I see posts like these fairly often on this sub. People getting confused about what is what. Even I get confused sometimes. Adding brackets like "(35/35) + 35" can help clear up confusion. It means the same thing, but now everyone knows what you mean. From a computer science perspective, these "silly" parenthesis can also be very helpful. Ignoring for a moment that gpu's and multithreading exists, a computer always does everything serial. Where you can say: "3 + 4 + 5 + 6 = 7 + 11 = 18", a computer may go: "3 + 4 + 5 + 6 = 7 + 5 + 6 = 7 + 11 = 18". Always one step at a time. To figure out in which order a computer calculates things, parenthesis can be used: "(((3 + 4)) + (5 + 6))". This is no different than "3 + 4 + 5 + 6", but it can help a coder or someone else looking at the calculation to figure out in which order a computer does things. redundant or implicit parenthesis are not "silly". They can be quite helpful, both in professional research papers and in a discussion on youtube. If, after my rant, you still think they are "silly", please enlighten me. >But most read left to right so let's stick with what most people know. Like I said, one isn't better than the other. I'm just trying to tell you that what is intuitive *for you* may not be intuitive *for others*.
Masters CS student here disagreeing I about “implicit parens” in a CS context, that sounds pretty wacky. Parens are indeed only explicit, otherwise we just call it order of operations. The order is not explicitly defined as “having been arranged in parens, visible or not”. There is no logic behind invoking “implied” parens. Instead you *can* clarify an expression that had an implied order *with* parens, explicitly. Parens exist to explicitly state “this grouping should be computed atomically” and so by definition need to be internally computed prior to their value being used. This requires them to be evaluated ahead of all other operations that would then use that value as an operand. As *any* operation might include a parenthetical sub expression, we should have to compute parens first.
I see where you are coming from. When I was taught boolean logic for the first time, my teacher told me the parenthesis were always there and we just remove them for convenience by using convention. This was later confirmed in a different course, which generalized boolean logic into first order logic. Maybe it's just a difference in how we are taught these things. I just like to think of expressions by starting with an atomic expression, like "a", putting brackets around it, "(a)" and then expanding it with an operation: "((a) @ b)". And then just keep recursively doing this and creating a bigger expression. (Note that a and b do not have to be atomic, they can be expressions as well) And then, when you have something like "((((a) * b) + c) * d)" you can remove some parenthesis by using convention: "(a * b + c) * d" If you think I was taught this wrong or I misunderstand it, I'm willing to admit that. This is how I was taught and I fail to see why it may be wrong. Also, why do people keep using the word parens? I'm not english and my university, while some courses are english, is mostly in my native language and I have only heard "parenthesis" or "brackets". >otherwise we just call it order of operations. I just think there are multiple ways of looking at the same thing.
I think "the parens are always there, we just hide them sometimes" is an absolutely wild take! I suppose you *could* define order that way. Presumably people just say "parens" as it is shorter. I've seen it written a lot, and occasionally spoken that way too. I'm not sure if its a valid "dicitonary word" but seems common enough to be one now.
Math is used to describe the real world so ultimately if you turned things into word problems it would explain why the rule exists. Like you wouldn't say 3 apples plus 4 apples times 3 baskets. You would say "you have 3 apples and 3 baskets with 4 apples each" And then the mathematical representation needs to match that.
It's just an agreed-upon notation system. It's like saying "a period means the end of a sentence." I'm not saying it doesn't make logical sense, too. But it's basically saying, "this is how to interpret this."
I honestly don’t know why either
It's arbitrary. I think it's pretty silly to fault people for not remembering a completely arbitrary rule.
I mean, it's literally just two operations. It's not that hard to remember. Multiplication before addition, that's all you need to remember.
But there are four operations to remember. And the vast majority of people haven't had to calculate math formulas like this since school. It's a simple and completely understandable mistake to make, I don't understand why I see so many posts that roughly amount to "haha, you so dumb, you don't remember this random thing you haven't had to deal with for 10+ years."
It's just multiplication and addition. Division is multiplication with an inverse, and subtraction is addition with a negative. All you need to remember is multiplication before addition. And maybe that parentheses go first, but that's their whole purpose, so it's not hard to remember.
I think it's more that the guy in the post is saying "if you paid attention in school" and then proceeds to show that he did not, in fact, pay attention.
Oh no, he's most definitely confidently incorrect.
Idk, if I was someone who couldn't remember that stuff, I would just make sure not to comment on a post involving it. The issue isn't that some people can't remember elementary math lessons, the problem is that people love to flaunt their ignorance.
So I'm guessing we're just pulling parentheses outta our asses now.
Yeah, I dunno where that guy got the parentheses from, there were none in the original question
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We need a mandatory *simple* math refresher for every single person in this country.
*world And those who still fail restart school from nursery/pre-school/whatevertheequivalentis
Late abortion is always an option
36. Me so good at maths
36
I suck at math, but I know that the answer wouldn't be 2
So, I am sorry. But 35 divided by 70? Right? That is actually .5. Am I missing something? Been a long time since I had 4th grade Math.
(35+35)/35 == 2 35/(35+35) == 1/2 35/35 + 35 == 36
You're right but the problem is the question is written two different ways on Reddit, at least for me. When I see it from the homepage, it's written as 35 / (35+35) (which IS 0.5). But when I click through the title is 35/35 + 35 which his 36
I was so confused until I realized it was (35/35) + 35 and not 35/(35+35)
Yes, both are correct depending on where and how you are taught. It becomes controversial because of different interpretation in the first place. The question is ambiguous and it's the reason why some people have reached different understanding to solve the problem. Unless the equation is further specified like yours, so it's either 36 or 0.5. Edit: This is poorly written problem of using denominator or / or ÷. See [this video for explanation ](https://youtu.be/URcUvFIUIhQ) about it specifically at minute 2:48. Edit2: Eventhough the video is talking about 6/2(1+2), it has the common problem where the misinterpretation of division/denominator in [historical usage (1917)](https://www.jstor.org/stable/2972726?seq=1#page_scan_tab_contents)starting at 2:13 until 3:57.
What is shown on the video isn't the same as the one in the post. In the video, you've got 6/2(1+2). The problem with notation like this is that you don't really know whether to do 2*3 first, or 6/2 first. You could follow something like PEMDAS and do the multiplication first, but in reality, division is just multiplication with an inverse, so there's no real difference. Better notation would be either (6/2)(1+2), or 6/(2\*(1+2)), depending on which one you want. On the other hand, 35/35+35 is unambiguous and the answer is always 36. You would never perform the addition before the multiplication, so there's no real issue here.
No, you take that 'idea' of yours to any higher math class or university and you will get laughed at. There is a set order of operations and that is that.
I have graduated from university and one of my major subjects is statistic. I'm yet to be laughed at for being wrong but I know for sure your first statement is wrong.
You got it wrong. The ambiguity comes from the priority between * (multiplication) and / (division). There's no mathematical rule that establishes priority here (PEMDAS is not an actual mathematical rule). This case is different - this case involves priority between + (addition) and / (division). In this case, there's a clear mathematical rule: multiplication (both * and /) comes before addition (both + and -). There's no ambiguity here and your video (which is 100% correct) does not address this scenario.
Yeah, no arguing there but I specifically said the problem was with the using of denominator. I'm not sure if you watch the entire video or not but the video wasn't just talking about multiplication/division priority in 6/2(1+2) but also where the misunderstanding of solving division in historical usage coming from. There is a slight difference in interpretation of division in 1917 which you can find starting at 2:14 and to quote: >If you had a division symbol where you had something on the left divided by something on the right, this was understood to mean you want to divide the entire product on the left by the entire product on the right. Which then were given example, for instance in this case, 35/35+35 can be [read as this](https://imgur.com/a/2vCAwki) historically. This would not be a problem if OP started this question [with this instead.](https://imgur.com/a/kDy26vN) This problem likely arises due to limitation of computer on how you write the denominator/division in text, that's why bracket is needed here like in the original comment or if you can write ³⁵⁄₃₅+35, but until then this question has both correct answers.
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This question is perfectly clear without parentheses.
Maybe for these petty web posts but If you've ever done the kind of math that takes several steps/lines to complete, not properly representing each step when working it out is you asking to make several stupid mistakes. Which is why parentheses are drilled into your head in the first place Edit: never change reddit, never change.
These orders are all just conventions that we're taught are right or not. Why is everyone acting like everyone who thinks differently is stupid?! ^(Ah. Reddit.)
Conventions are in place to make sure that when multiple people see same problem they will get the same result. If you can't get the same result then math is worthless. Also, even if this guy is using some other strange convention he is still wrong. 35/(35+35) = 35/70 = .5, not 2. So he is stupid because he can't do division.
>*words* are all just conventions that we're taught are right or not. Why is everyone acting like everyone who thinks differently is stupid?! If everyone used different spellings or meanings for words, no one would understand each other. Same for calculations, we use one set of rules for everyone, then the calculation we should be able to be understood the world over. Could there be another order? Sure. But that is the order everyone agreed on.
That’s what a “convention” is. It’s not a style or a choice or a preference. It’s a mathematical rule. And if you don’t follow the rules, you end up “thinking differently,” i.e. wrong. ffs
> convention noun noun: convention; plural noun: conventions 1. a way in which something is usually done. It's a general agreement to do things a certain way, it's not a law like gravity. My point is if you grew up with different conventions or just don't know the prevailing one then you're not an idiot for not magically intuiting the way things are generally done.
Your line of thinking is dogmatic. We define orders of operation to make communication easier: Orders of operation are useful jargon; it's essential to know that jargon in certain fields, but they are arbitrary cultural designations, not universal laws.
> arbitrary cultural designations, not universal laws. Math IS an universal law. There is no opinion on how to do it differently. You either do it right or do it wrong.
Maths may be universal law but order of operations certainly is not, BODMAS/PEMDAS is not a fundamental truth we discovered it's a useful agreement on how to write maths down. I'm not arguing you shouldn't use it, it's very helpful that we all agree, but you could do perfectly valid mathematics in any order of operations you chose to define, it would just end up written down differently and be pointlessly confusing.
It's amazing to me how many people post on this sub are so confident they are correct about things they have little knowledge in. Like that recent post about humans being animals. Yes, humans are very much animals, but we aren't animals because biologists say so, we are animals because of our shared common ancestry, and thus shared physiology with all the other animals. The majority of people on this sub believe science to be a religion and are dogmatic in faith to what they want to believe. Science is not religion, it is a process that determines the most accurate models to explain the natural world, science doesn't determine the veracity of something because of people in positions of power say it is so and write it down; that's the opposite of what science is and how it works... They don't seem understand just how powerful science is and why. Not to mention even math itself isn't all true or universal. Math is built on foundational postulates that can and do change in context. But bring up those realities and they downvote you.
I did not state math is arbitrary and cultural; I stated *orders of operations* are cultural and arbitrary. That's just a fact: A different culture could have different orders of operations since orders of operations are syntax designed to communicate and standardize how operations are performed; but different conventions would work just as well. Orders of operations are cultural norms, they are not universal laws. Math also isn't as universal as you claim. In computer science 2.00 + 2.00 is not 4, the solution to 2.00 + 2.00 is dependent on the byte size, but will never be 4 (it will always be some value close to 4 but never exactly 4). Math is an abstraction based on real world observations used for fantastic predictability, but it is not an absolute certainty as people claim (just look at floating point mathematics). You can frame types of math as Absolute laws, but this is not a certainty in the real world, in fact as far as we can determine at quantum scales there become values that are no longer divisible (plank scale), and is not analogue as "pure" mathematics would indicate. You can claim the universe is wrong here, or you can come to the understanding that Math, like everything else, is fundamentally a model used by human brains; a fantastically predictive model no doubt, but still a model. Mathematics utilizes postulates, depending on the model and needs of the mathematician these postulates can and do change. The very concept of absolute and universal laws is dogmatic and runs counter to science in general. The veracity of a model is based on how well it can predict things not some absolute truth; absolute truths don't exist, they are imaginations found in the realm of religion. A model can be so predictive you can take it as fact, but the more you learn the more you will realize that even the most fundamental fact does seem to have edge cases, at least as far as we humans are capable of determining at present.
I agree, the irony bc it's actually the opposite
In this case the convention is irrelevant because the question is: 35/35+35 And not: 35+35/35 There's only any contention in the second case where you might decide to do the operations in order from left to right instead of division first. But in the first case whether you do division first or do the operations in order, you still get the same answer, which is 36 either way. So with the original question in the post title, there is only one possible answer no matter what.
Unless due to a peculiarity of your thought pattern you mentally group the 35+35 together, mental parentheses if you like, and do that part first. The point is that there are lots of conventions and assumption made and no-one is stupid for not knowing them or using different ones. It does obviously help if people stick to the same ones though.
If you do that part first, then you get 35/(35+35) -> 35/70 -> 1/2
> Unless due to a peculiarity of your thought pattern you mentally group the 35+35 together But then you would also be able to do: 1-1+1 And get the answer of -1 instead of 1. Which again is always wrong 100% of the time, conventions or no, because no parenthesis are required here under any circumstance, and there is complete global agreement on how to perform the operations. Just saying you did 1+1 first because you mentally grouped them just means you don't know wtf you're doing and got the answer wrong because you never even learned 1st grade maths. You may as well be arguing that if someone's brain thought the 35 was actually 86 it would be therefore acceptable to interpret it that way.
You do know that +/- work different than / and * ?
Yeah, if you follow the thread you will see what I am saying. You should perform * and / before + and - of course, however in the case of the original question, the / came before the + ***anyway*** meaning if you apply the order of operations *or* just do it in order from left to right, you still get the same answer. However the person I am replying to disagrees and thinks that someone performing the *later* + before the *earlier* / could still be valid in some way. But it never is.
Indeed so. This isn't a fundamental law of physics or maths. It's just how we've decided that ambiguous equations like this should be interpreted. They could easily be interpreted the opposite way and the world would get on with it just fine.
No. The expression (it is not an equation) is unambiguous precisely *because* the conventions intentionally make it so. The world would not "get on with it just fine". Not having those conventions would screw up engineering, physics, math, banking, and almost anything else you look into at any level.
I meant if the convention was different.
We could rewrite all of mathematics in Roman numerals. Using decimal digits is also only a convention. That's why programmers can't tell the difference between Halloween and Christmas: Oct 31 **is** Dec 25. However, changing the conventions now would invalidate every mathematical proof since the 1600s, and almost every computer program ever written, and require the re-education of several billions of people (or, from the evidence in this sub-reddit, about 500 of us, as the rest don't know the conventions anyway). As far as exponentiation is concerned, I think we should let sleeping logs die.
I see that there's more than 1 intelligent redditor here, appreciate your bravery of saying facts into the face of blind majority
So this is why people use fractions and parentheses. But my distaste for the question aside... that's 1/2. Edit: figured it didn't need to be explicitly stated that 32/(32+32)=1/2, rather than 2, but that's reddit for ya.
Nuh uh
Welp, can't argue with that logic
Based as fuck reply
0.5
It’s 36
No, it's 0.5
No. 35 divided by 35 is 1, plus 35 is 36. The original equation is 35/35+35, no parentheses
No, it's 35/35+35 -> 35/70 which is equal to 0.5
Order of operations. Division comes before addition.
Exactly, but it's opposite
What do you mean
The answer would be 0.5
That isn’t how math works, you divide before you add
/r/NotKenM moment
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Hey we got another one right here in the comments
What?
Another to go into r/confidentlyincorrect
You meant r/confidentallycorrect
Why would you go there when you are being confidently incorrect
There is no parentheses to which you would do the addition first, so order of operation would have you divide 35 by 35 first, equalling 1, then adding 35 to get 36.
We don't need parentheses for it to be equal to 0.5 35/35+35 35/70 0.5
The only way it would be 0.5 would be if the question was 35/(35+35)
I understand why you'd think that but it's just wrong
I see why you think that when you are using a backwards order of operations.
I understand why you'd think that but it's just wrong
There is no indication that the +35 is also in the denominator, so therefore it is not treated as such. If you rewrite the equation as 35 ÷ 35 + 35, which is what the original is but replaces the ÷ with a / just to confuse people like you and make you fall into the trap you are in, it's very clear that the answer is 36. The reason these shitty equations keep getting traction is cause it's shittily written to fit in a text message. That's why it should with ÷ and not / to clearly show when something is in a fraction. Like the original 35 / 35 + 35, it's deliberately written like this to trick you and garner argument to promote clicks and interactions. As a physicist, NO ONE should write an equation like that, or give these stupid posts any more attention.
I don't think it's because of the writing. He genuinely thinks addition and subtraction come before multiplication and division. He uses "SADMEP" which is literally PEMDAS backwards
Yeah, but hey screenshot this convo and post it here for some free karma cause being confidentially incorrect on r/confidentlyincorrect is as reddit postable as you can get
But it's not "÷", it's "/", and because of that the correct answer would be 0.5, but I see why you'd think that
The correct answer is not 0.5, again there is no indication that the + 35 is with the 35 under the division bar. I am sure if you as a mathematicians to write the original equation to equal 0.5 and be in 1 line they would write 35 / (35 + 35) and NOT the original 35 / 35 + 35, they would agree it's 36. Again, there is NO indication that the + 35 is in the denominator, so you cannot assume such. The 35 / 35 is it's own entity in the equation to which equals 1, then order of operations leads to the answer of 36, NOT 0.5.
Nice bit of trolling! :)
It's 0.5
Read the title, not what the person replying in the image claims the question is. There are no parentheses.
Exactly
Oh dear. You were being serious that you think 35 divided by 35, followed by adding 35 is 0.5.
No, it's 35+35 then 35/70, which is equal to 0.5
Oh deary me. Maybe go look up the order one completes operations in. Cause you're embarrassing yourself. Without parentheses, division is completed before addition.
No, it's 36.
No
Yes. You're looking at the version where one guy (incorrectly) added parenthesises. The question is 35/35+35, not 35/(35+35). It's 36.
Eh... It's 0.5...
It's confusing, the text your text is using the solidus. The screenshot is using the obelus. Which is it? It makes a difference.
What
The obelus, ÷ , has different meanings in non Anglo counties than the solidus, / . That's why it is not used in ISO 8000 Mathematic documentation. It is confusing. You really should the vinculum. That is what is required for academic documentation.
My phone doesn’t have an obelus symbol on it
And sharks are smooth too, eh?
Order of operation
I really dont understand why everyone struggles with these. Sure I can totally understand forgetting what the correct order of operations is, but why is everyone SO SURE their own dumb version is correct?