You must log in or # to comment.
I feel like I am getting trolled
Isn’t 17 the actual right answer?
Exactly
So it’s just an unfunny meme?
I think it’s meant to play with your expectations. Normally someone’s take being posted is to show them being confidently stupid, otherwise it isn’t as interesting and doesn’t go viral.However, because we’re primed to view it from that lens, we feel crazy to think we’re doing the math correctly and getting the “wrong answer” from what we assume is the “confident dipshit”.
There’s layers beyond the superficial.
I fell for it. It’s crazy to think how heavily I’ve been trained to believe everything I see is wrong in the most embarrassing and laughable way possible. That’s pretty depressing if you think about it.
As most memes are.
More like a sad realization of the state of (un)education in some parts of the so-called civilized world.
You laugh not to cry.It’s engagement bait.
deleted by creator
Yeah I know that. But I was feeling confused as to why it was here. That’s why I was feeling trolled, because it made me doubt basic math for being posted in a memes community.
They did the joke wrong. To do it right you need to use the ÷ symbol. Because people never use that after they learn fractions, people treat things like a + b ÷ c + d as
a + b ----- c + dOr (a + b) ÷ (c + d) when they should be treating it as a + (b ÷ c) + d.
That’s the most common one of these “troll math” tricks. Because notating as
a + b + d - cIs much more common and useful. So people get used to grouping everything around the division operator as if they’re in parentheses.
Because people never use that after they learn fractions,
Yes they do, because not every division is a fraction
I already said he was wrong about that. Quoting him saying it doesn’t change that he’s wrong about it
Take it up with Berkeley then.
Treat
a + b/c + dasa + b/(c + d)I can almost understand, I was guilty of doing that in school with multiplication, but auto-parenthesising the first part is really crazy take, imoThat’s a really odd way to parse it.
a + b ----- c + bTreat a + b/c + d as a + b/(c + d)
No don’t. That rule was changed more than 130 years ago. a+b/c+d=a+(b/c)+d, Division before Addition
Alternatively, the poster calculated the wrong answer, thus assuming this guy was wrong.
Gotcha gotcha, sorry
Presuming PEMDAS is our order of operations and the 5 next to the parentheses indicates multiplication…
2+5(8-5) -> 2+5(3) -> 2+15=17
Other than adding a multiplication indicator next to the left parentheses for clarification (I believe it’s * for programming and text chat purposes, a miniature “x” or dot for pen and paper/traditional calculators), this seems fine, yeah.
…I worry about how many people may not understand how to solve equations like these.
That’s not even an equation, just basic arithmetic
Technically not algebra, right? Algebra is where you move things around and solve for variables, and that kind of thing. This is just arithmetic.
You’re right, that’s what I meant. Fixed it, thanks!
Technically not algebra, right?
No, it actually is Algebra. The Distributive Law isn’t taught to students until they start on Algebra.
This is just arithmetic
There’s no a(b+c) in Arithmetic.
I don’t think you’re right. The wiki page literally uses a similar equation as an example of “elementary arithmetic.” It also uses a similar one, but with variables, as an example in “elementary algebra.” That implies that yes, this is arithmetic, and the introduction of variables is what makes it algebra.
It doesn’t matter what course finally teaches it to you. That could be just out of convenience, not by definition part of that domain. It’s been ages since I took it, though I could swear I learned this in pre-algebra (meaning before algebra), or earlier. I could be wrong on this though. Again, it’s been a very long time.
I don’t think you’re right
You don’t think Maths textbooks are right??
The wiki page
is full of disinformation. Note that they literally never cite any Maths textbooks
as an example of “elementary arithmetic.”
And whichever Joe Blow My Next Door Neighbour wrote that is wrong
as an example in “elementary algebra.”
Algebra isn’t taught until high school
That implies that yes, this is arithmetic,
No, anything with a(b+c) is Algebra, taught in Year 7
the introduction of variables is what makes it algebra
and the rules of Algebra, which includes a(b+c)=(ab+ac). There is no such rule in Arithmetic.
It doesn’t matter what course finally teaches it to you
It does if you’re going to argue over whether it’s Arithmetic or Algebra.
not by definition part of that domain
The Distributive Law is 100% part of Algebra. It’s one of the very first things taught (right after pronumerals and substitution).
It’s been ages since I took it
I teach it. We teach it to Year 7, at the start of Algebra
You’re very rude. Also, Ill informed, and you think you’re smarter than you are. For example, this:
as an example in “elementary algebra.”
Algebra isn’t taught until high school
Elementary doesn’t mean elementary school. Do you think elementary particles are the ones they teach you in elementary school? Lol. Elementary means fundamental or basic.
You’re very rude
What do you expect to happen when you call a Maths teacher wrong about Maths?
Ill informed
Maths teachers are ill informed about Maths?? 😂
Elementary means fundamental or basic
Which therefore contradicts your argument about it being part of Arithmetic, which is taught in elementary school, Algebra isn’t
Fair enough, I’ve heard “math problem” and “math equation” used interchangeably.
Also you would be surprised how many people do not know basic algebra, at least in the US rofl
Algebra has horrible syntax. Way too much implications.
Implications or assignment? They didn’t specify notation.
Implications or assignment?
Umm, neither?? 😂
They didn’t specify notation
a(b+c)=(ab+ac) is taught in Algebra, The Distributive Law, it can’t mean anything else - it’s the reverse operation to Factorising ab+ac=a(b+c).
I know. I was clowning on the dude mad about the arrows by offering one of numerous other meanings outside Boolean Algebra that sounded even more absurd in that context.
I know. I was clowning
Ok, fair enough. Some people seriously believe completely wrong things. A smiley goes a long way to showing intent
That’s not even an equation, just basic arithmetic
Basic Algebra actually. Students aren’t taught the Distributive Law until they start on Algebra
Multiplication sign is not required in situations like this. Same with unknowns - you don’t have to write
2*x, you just write2x.the 5 next to the parentheses indicates multiplication
No, it indicates Distribution, a(b+c)=(ab+ac), 5(8-5)=(5x8+5x5).
5 isn’t a valid function name, is obviously the right answer.
It could be a Church Numeral
5 isn’t a valid function name, is obviously the right answer.
5 is a coefficient of the Term 5(8-5) is the correct answer
I got some people really angry at me when I suggested writing some math expression with parenthesis so it would be clearer. I think someone told me that order of operations is like a natural law and not a convention, and thus everyone should know it or be able to figure it out.
I sometimes like to add unnecessary parentheses or brackets to section things off and improve legibility, but I don’t do any math stuff collaboratively, so I have no idea whether others would find that disruptive or helpful.
I mean, there are very few ambiguous cases when you know how the order of operations works.
I mean, there are very few ambiguous cases
There are precisely none which are ambiguous
Using parenthesis can really help if you want to simplify a term or need to rewrite something. I do that all the time because a lot of times you then can just cross stuff out fast on equations or get a common term that just has some factor instead of having a convolutet equation.
so it would be clearer
That’s because it’s already clear as is, as per the rules of Maths.
I think someone told me that order of operations is like a natural law
It’s a natural consequence of the definitions of the operators. e.g. Multiplication is shorthand for repeated Addition - 2x3=2+2+2 - so if you don’t do it before addition you end up with wrong answers. The order of operations rules is in fact just breaking everything down into Addition and Subtraction and then solving from there.
not a convention
There are some conventions, like left to right, but in that case that’s only because students tend to make mistakes with signs when they don’t go from left to right, so it’s there to preserve teachers sanity.
That’s because it’s already clear as is, as per the rules of Maths.
More people evaluate
2+3x4incorrectly than2+(3x4). So, no, your answer does not hold up to my observed reality. You can throw as many “well technically” and “well actually” as you want, but that’s not going to fix the bug or make a pr.More people evaluate 2+3x4 incorrectly than 2+(3x4)
The people who have forgotten the rules of Maths, and the mnemonics even! 😂
So, no, your answer does not hold up to my observed reality
So try observing a real Maths textbook then. Students have no trouble at all with this, only adults who’ve forgotten the rules.
Adults who have forgotten the rules who I work with and read/write code where it’s important. In the real world.
This is like some pure maths vs real life engineering cliché.
You’re either being deliberately obtuse or you’re painfully naive.
Adults who have forgotten the rules who I work with and read/write code where it’s important
And as a consequence of that, MathGPT is the only e-calc which gives correct answers to order of operations! 😂
This is like some pure maths vs real life engineering cliché
It’s a Correct Maths vs. Programmers who have forgotten the rules cliche
You’re either being deliberately obtuse or you’re painfully naive
Neither, I’m a Maths teacher
I like and respect teachers, but I’m a software developer and I’m telling you that adding extra parenthesis often adds clarity and makes the whole process smoother. You exist in a whole other context that has norms and assumptions that do not apply to what I’m talking about.
You being technically correct is irrelevant.
I’m a software developer
So am I
adding extra parenthesis often adds clarity
Everyone I’ve seen add Brackets to it has done so in the WRONG place and given WRONG answers. Again this is an issue of programmers not checking the rules of Maths
that do not apply to what I’m talking about
The rules of Maths always apply to all Maths
deleted by creator
Any PEMDAS enjoyers in chat?
(* (+ 2 5) (- 8 5))Hope some LISP can clear this up
Edit:
( + 2 ( * 5 ( - 8 5 ) ) )Is this a meme? Shouldn’t it be
( + 2 ( * 5 ( - 8 5 ) ) )Damn you are right haha.
Mine evals to 21.
Let’s not do engagement bait here 😭
I don’t know how we’ve managed to get to 2025 and there’s still apparently people who haven’t seen a thousand shit PEMDAS posts already
Hrmm.
I read that as resulting in 21.
My education system did fail me.
I plugged that into ghci as 2+5*(8-5), and it says 17.
:(
I did (2+5)*(8-5).
Doh.
[Edit: (Double doh! Mistyped that here as 5+2. XD)]
You do parenthesis first and then multiplications and then sums, you did parenthesis, then sums, then multiplications, wich is wrong.
then multiplications
There aren’t any, only Addition and Brackets (and Subtraction inside Brackets)
Uh huh.
plugged that into ghci as 5+2*(8-5), and it says 17.
You might want to report that error. Or, did you mean 2+5*(8-5)?
Oops! Typo. School failed me hard!
[Edit: Thanks. Corrected that.]
I did (2+5)*(8-5).
The problem is you can’t just add parenthesis willy nilly, that breaks the whole equation!
Obviously the answer is 2+x(y)
And even if you don’t simplify it to y the end result is the same
2+x(y-z) = 2+xy-xz
The high-and-mightiness quotient in this thread is reaching critical levels
Let’s keep it easy. There’s 2 + all the other number who results in 15 = 17.
Someone may mistake by doing 2+5 then the rest of the operation, resulting in 21. But is wrong.
deleted by creator
What? A number next to parenthesis always means multiplication. Are people really not taught this anymore?
What? A number next to parenthesis always means multiplication
No, it means distribution, a(b+c)=(ab+ac)
Are people really not taught this anymore?
They’re taught distribution yes. It’s only adults who’ve forgotten the rules of Maths who get these wrong
Counterpoint:
If kids where taught how to solve them properly we wouldn’t need to dumb down equasions.
If kids where taught how to solve them properly we wouldn’t need to dumb down equasions
They are taught how to solve them properly. It’s only adults who’ve forgotten the rules of Maths who get them wrong
Why should anyone do that, an implied multiplication is the normal thing you learn in (I think?) somewhere between 5th to 7th grade. You only add an operator if it’s something else. It’s as basic as PEMDAS.
an implied multiplication
There’s no such thing. It’s a Term/Product.
is the normal thing you learn in (I think?) somewhere between 5th to 7th grade
Yes, you learn that it’s a Term/Product in Year 7
You only add an operator if it’s something else
You never add an operator, or you end up with wrong answers.
Aaah, got it. So if I see something like “5-(2+4)” I will just remove the subtraction operator and call it a day. Smartman on the internet said so. 🥴
Also casual reminder not everyone on the internet is a native english speaker. Everyone but you knew what was meant.
So if I see something like “5-(2+4)” I will just remove the subtraction operator and call it a day
Nope. Never said anything of the sort.
Smartman on the internet said so
No I didn’t, but nice try at a strawman 😂
not everyone on the internet is a native english speaker. Everyone but you knew what was meant.
There is no such thing as “implied multiplication” in any language. They are called Terms/Products in whatever language that book is using.
Put a goddamn function sign for the parenthesis
Why?
Don’t assume everyone just knows what to do with the parenthesis alone
Well, everyone was taught what to do with it in high school.
This is an antimeme
That’s so evil and subtle. It took me multiple attempts to figure it out. You have to have quite the sharp eye to realize: no, you do not stop at calculating the numbers in parantesis first. You don’t add the resulting numbers, there is no +/- operator, so the number in parantesis is the power of the number before it. But wait! if You calculated 2+5 = 7 * 3 and hot 21, you are wrong. Remember that multiplication goes first, so it’s: 2+5(8-5) = 2+5*3=2+15=17
is this an attempt at a copypasta
No, I’m trying to explain something while high on brain damage.
I appreciate the effort
Remember that multiplication goes first
Remember Brackets are solved first - there is no Multiplication
so it’s: 2+5(8-5) = 2+5*3
No, so it’s: 2+5(8-5) = 2+(5x8-5x3), a(b+c)=(ab+ac).
Was anyone else ever taught it as BOMDAS as opposed to BODMAS?
There’s no difference.
Addition and subtraction are the same operation, multiplication and division are the same operation.
So:
BO(MD)(AS) == BO(DM)(AS)
EDIT: in order to stop confusing people, it should just be: BOMA.
multiplication and division are the same operation
No they’re not, but they are both binary operators.
in order to stop confusing people, it should just be: BOMA.
Leaving out D and S confuses people about where to do them in the order. It’s intended to be used as a checklist
You already said that to me. I replied here.
You already said that to me
And you’re still ignoring it
What do you mean? I replied to it…
What do you mean? I replied to it…
Where you, yet again, ignored that I told you what you said is wrong, as per Maths textbooks
Yeah, I was taught BOMDAS here in Australia.
I was taught BODMAS in Australia
BODMAS (or BEDMAS), not BOMDAS. (unless they did that in some random state). I’m an Australian Maths teacher
Or it was some random teacher. Or it was more than fifteen years ago. I dunno, it was just what I was taught.
Or it was some random teacher
Yeah, maybe. My Year 7 students, who have come fresh to me from Year 6, use BEDMAS, and I teach BEDMAS for consistency (I also think it’s a better acronym anyway - think of a massive 4-poster bed to ingrain the idea of BED-MAS)…
I was taught only Brackets Division Subtraction Multiplication at the local dungeon.
(I still have the student loans to prove it.)
Was anyone else ever taught it as BOMDAS as opposed to BODMAS?
I don’t think so, and I’ve seen Maths textbooks from all over the world. Only the U.S. wants to reverse the order of DM from everyone else’s acronym. 🙄
