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I feel like I am getting trolled
Isn’t 17 the actual right answer?
Exactly
So it’s just an unfunny meme?
Some people insist there’s no “correct” order for the basic arithmetic operations. And worse, some people insist the correct order is parenthesis first, then left to right.
Both of those sets of people are wrong.
Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I’d hope).
So they’re mostly telling you they only remember as much math as a small child that barely passed math exercizes.
If you have a bunch of unparenthesized addition and subtraction, left to right is correct
If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.
1 + 2 + 3 = 3 + 2 + 1
True, but as with many things, something has to be the rule for processing it. For many teachers as I’ve heard, order of appearance is ‘the rule’ when commutative properties apply. … at least until algebra demands simplification, but that’s a different topic.
order of appearance is ‘the rule’ when commutative properties apply
That’s because students often make mistakes with signs when they do it in a different order, so we tell them to stick to left to right
If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.
Right, because 1-2-3=3-2-1.
You flipped the sign on the 3 and 1.
I did not flip any signs, merely reversed the order in which the operations are written out. If you read the right side from right to left, it has the same meaning as the left side from left to right.
Hell, the convention that the sign is on the left is also just a convention, as is the idea that the smallest digit is on the right (which should be a familiar issue to programmers, if you look up big endian vs little endian)
If that’s your idea of reversing the order, then you’re not talking about the same thing as SpaceCadet@feddit.nl. They’re talking about the order of operations and the associativity/commutativity property. You’re talking about the order of the symbols.
I did not flip any signs
Yes you did! 😂
merely reversed the order in which the operations are written out
No, merely reversing the order gives -3-2+1 - you changed the signs on the 1 and 3.
If you read the right side from right to left, it
Starts with -3, which you changed to +3
it has the same meaning as the left side from left to right
when you don’t change any of the signs it does 😂
Hell, the convention that the sign is on the left is also just a convention
Nope, it’s a rule of Maths, Left Associativity.
Right, because 1-2-3=3-2-1
No, 1-2-3=-3-2+1. You changed the signs on the 1 and the 3.
addition and subtraction, left to right is correct
You can do addition and subtraction in any order and it’s still correct
PE(MD)(AS)
Now just remember to account for those parentheses first…
PE(MD)(AS) Now just remember to account for those parentheses first
Those Brackets don’t matter. I don’t know why people insist it does
Well, this is just a writing standard that is globally agreed on,
The writing rules are defined by humans not by natural force
(That one thing and another thing are two things, is a rule from nature, as comparison)Save yourself the trouble - Smartman Apps is a crank. They categorically will not comprehend the difference between the notation we made up and how numbers work. Dingus keeps saying ‘animals can count’ like that proves parentheses-first is completely different! from distribution.
Why’d Russel and Whitehead bother with the Principia Mathematica when they could just point to Clever Hans?
this is just a writing standard that is globally agreed on
No, it’s a universal rule of Maths
The writing rules are defined by humans not by natural force
Maths is for describing natural forces, and is subject to those laws
That one thing and another thing are two things, is a rule from nature
Yep, there are even some animals who understand that, and all of Maths is based upon it.
Some people insist there’s no “correct” order for the basic arithmetic operations.
And those people are wrong
And worse, some people insist the correct order is parenthesis first, then left to right
As per Maths textbooks
Both of those sets of people are wrong
All Maths textbooks are wrong?? 😂
I mean, arithmetic order is just convention, not a mathematical truth. But that convention works in the way we know, yes, because that’s what’s… well… convention
I mean, arithmetic order is just convention
Nope, rules arising from the definition of the operators in the first place.
not a mathematical truth
It most certainly is a mathematical truth!
But that convention works in the way we know, yes, because that’s what’s… well… convention
The mnemonics are conventions, the rules are rules
The rules are socially agreed upon. They are not a mathematical truth. There is nothing about the order of multiple different operators in the definition of the operators themselves. An operator is simply just a function or mapping, and you can order those however you like. All that matters is just what calculation it is that you’re after
The rules are socially agreed upon
Nope! Universal laws.
They are not a mathematical truth.
Yes they are! 😂
There is nothing about the order of multiple different operators in the definition of the operators themselves
That’s exactly where it is. 2x3 is defined as 2+2+2, therefore if you don’t do Multiplication before Addition you get wrong answers
you can order those however you like.
No you can’t! 😂 2+3x4=5x4=20, Oops! WRONG ANSWER 😂
All that matters is just what calculation it is that you’re after
And if you want the right answer then you have to obey the order of operations rules
That’s a very simplistic view of maths. It’s convention https://en.wikipedia.org/wiki/Order_of_operations
Just because a definition of an operator contains another operator, does not require that operator to take precedence. As you pointed out, 2+3*4 could just as well be calculated to 5*4 and thus 20. There’s no mathematical contradiction there. Nothing broke. You just get a different answer. This is all perfectly in line with how maths work.
You can think of operators as functions, in that case, you could rewrite 2+3*4 as add(2, mult(3, 4)), for typical convention. But it could just as well be mult(add(2, 3), 4), where addition takes precedence. Or, similarly, for 2*3+4, as add(mult(2, 3), 4) for typical convention, or mult(2, add(3, 4)), where addition takes precedence. And I hope you see how, in here, everything seems to work just fine, it just depends on how you rearrange things. This sort of functional breakdown of operators is much closer to mathematical reality, and our operators is just convention, to make it easier to read.
Something in between would be requiring parentheses around every operator, to enforce order. Such as (2+(3*4)) or ((2+3)*4)
That’s a very simplistic view of maths
The Distributive Law and Arithmetic is very simple.
It’s convention
Nope, a literal Law. See screenshot
Isn’t a Maths textbook, and has many mistakes in it
Just because a definition of an operator contains another operator, does not require that operator to take precedence
Yes it does 😂
2+3x4=2+3+3+3+3=14 by definition of Multiplication
2+3x4=5x4=20 Oops! WRONG ANSWER 😂
As you pointed out, 2+34 could just as well be calculated to 54 and thus 20
No, I pointed out that it can’t be calculated like that, you get a wrong answer, and you get a wrong answer because 3x4=3+3+3+3 by definition
There’s no mathematical contradiction there
Just a wrong answer and a right one. If I have 1 2 litre bottle of milk, and 4 3 litre bottles of milk, even young kids know how to count up how many litres I have. Go ahead and ask them what the correct answer is 🙄
Nothing broke
You got a wrong answer when you broke the rules of Maths. Spoiler alert: I don’t have 20 litres of milk
You just get a different answer
A provably wrong answer 😂
This is all perfectly in line with how maths work
2+3x4=20 is not in line with how Maths works. 2+3+3+3+3 does not equal 20 😂
add(2, mult(3, 4)), for typical
rule
But it could just as well be mult(add(2, 3), 4), where addition takes precedence
And it gives you a wrong answer 🙄 I still don’t have 20 litres of milk
And I hope you see how, in here, everything seems to work just fine
No, I see quite clearly that I have 14 litres of milk, not 20 litres of milk. Even a young kid can count up and tell you that
it just depends on how you rearrange things
Correctly or not
our operators is just convention
The notation is, the rules aren’t
Something in between would be requiring parentheses around every operator, to enforce order
No it wouldn’t. You know we’ve only been using brackets in Maths for 300 years, right? Order of operations is much older than that
Such as (2+(3*4))
Which is exactly how they did it before we started using Brackets in Maths 😂 2+3x4=2+3+3+3+3=14, not complicated.
Social conventions are real, well defined things. Some mathematicians like to pretend they aren’t, while using a truckload of them; that’s a hypocritical opinion.
That’s not to say you can’t change them. But all of basic arithmetic is a social convention, you can redefine the numbers and operations any time you want too.
Social conventions are real, well defined things
So are the laws of nature, that Maths arises from
Some mathematicians like to pretend they aren’t, while using a truckload of them; that’s a hypocritical opinion
No, you making false accusations against Mathematicians is a strawman
That’s not to say you can’t change them
You can change the conventions, you cannot change the rules
But all of basic arithmetic is a social convention
Nope, law of nature. Even several animals know how to count.
you can redefine the numbers and operations any time you want too
And you end up back where you started, since you can’t change the laws of nature
There is no answer. Because there is no question.
Because there is no question
So Maths test says “2+3 ____”, and you write “that’s not a question” on the blank line?? 😂
That is a problem, tho
I know the solution
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.
My education system didn’t fail me, I failed it.
I’m sorry but isn’t this elementary school math?
In the rest of the world: yes.
In the US: I highly doubt it.
This is just basic math, if you can’t figure this out you’re probably 8 years old.
Probably some backwards-ass red state / red town shenanigans.
Math was always taught in my Blue cities. The atrocities of the US’s history was never left out of the curriculum.
We need to actually finish doing reconstruction and fix this country.
Fix? It’s a duster fire. It may be hard to deal with, but a total collapse and completely rebuilding it feels like the better solution to the problem (so not based on a constitution made in completely different times with muskets and without internet etc).
So you were taught math. What languages did you learn besides English? What history did you learn, just US or also of other countries and the rest of the world? And talking about the rest of the world, how much did you learn about that? Countries, cultures, cities, geographic features like mountains, seas, etc. and how they were formed? What religions were taught about? What about history of music and art?
In all fairness, I grew up in a small town in a very red state, but the education system there proved better than larger, more progressive parts of the state. The education I received was likely an outlier and not representative of the norm, but it did teach me that educators in an area do not necessarily mirror the rest of the population.
In the US: I highly doubt it
The issue in the U.S. isn’t Maths textbooks (same rules as everywhere else), it’s poor teaching. U.S. Maths teachers aren’t required to have any Maths qualifications, and they’ve been sliding in world rankings for more than a decade now.
Yeah, but even worse, you’re just talking about schools. You forgot about all the kids being home schooled, taught the earth is flat and an imaginary friend created everything in 7 days. Taught by parents who lack proper education themselves.
Also, it’s kinda obvious the rules of math aren’t different in the US. Even when they use an idiotic measuring system. If people don’t know how to use math properly, the issue clearly is the education and not math itself.
Yeah, but even worse, you’re just talking about schools
I’m talking about anyone at all in the U.S. is allowed to teach Maths without any Maths qualifications
You forgot about all the kids being home schooled
That happens in other countries too, and yet it’s the U.S. which has been sliding down the world rankings for more than a decade, the country that doesn’t require Maths teachers to have Maths qualifications.
Also, it’s kinda obvious the rules of math aren’t different in the US
That’s right, as proven by U.S. Maths textbooks
If people don’t know how to use math properly, the issue clearly is the education and not math itself
Partly right. there’s also people who just outright forgot the rules.
Partly right. there’s also people who just outright forgot the rules.
It doesn’t really matter, who needs math anyway? If the president can claim medicine prices will go down 1200%…
who needs math anyway?
Lots of people
If the president can claim medicine prices will go down 1200%
Did you miss seeing all the people who know Maths ridiculing him?
Definitely taught in parts of the US, it’s a regional thing though
Definitely taught in parts of the US, it’s a regional thing though
It’s a how good is your Maths teacher (who isn’t required to have any Maths qualifications) question. The rules are the same everywhere.
It became a meme a few years ago, people would post problems like this and argue about whose was right, as if there were no objective truth. It hurt to watch.
Arguably, there is no objective truth, since the symbols and rules of mathematics are assigned arbitrarily, and are basically a social contract, just like language!
…Wait, that means there’s no objective meaning of “objective”, crap
Arguably, there is no objective truth
Yes there is, just look in Maths textbooks
since the symbols and rules of mathematics are assigned arbitrarily
The signs are, the rules aren’t.
are basically a social contract, just like language!
Nope and nope. It’s a tool for calculating things, nothing like a language at all.
no objective meaning of “objective”
There is, in a dictionary, just like the rules of Maths are in Maths textbooks
ya this one is super unambiguously PEMDAS, the one that has more of an argument is the one with the division of whether
a/b(c)isa / (b * c)or(a / b) * cya this one is super unambiguously PEMDAS
Spoiler alert: they all are
the one that has more of an argument is the one with the division of whether a/b© is a / (b * c) or (a / b) * c
No it doesn’t, The Distributive Law, a(b+c)=(ab+ac), thus a/b©=a/(bxc).
I’m sorry but isn’t this elementary school math?
No, high school. The Distributive Law isn’t taught until Year 7
PEMDAS bitches.
I never ran into PEMDAS while growing up, in Sweden I’ve always been taught of it as the following order of operations:
- P
- E & Roots
- M & D
- A & S
e: Wanted to see if this is a thing in English.
It’s interesting that you can somewhat tell where you are from based on this, I learned it as BODMAS
O - oxponent?
O - oxponent?
To the Order of. 2² is 2 to the order of 2
Orders.
Brackets, Orders (powers and roots), Division, Multiplication, Addition, and Subtraction
Division, Multiplication, Addition, and Subtraction
This is fucking so many people over… It should be limited - like Orders - to only Multiplication and Addition.
Because division is the same operation as multiplication, and subtraction is the same operation as addition, and they have the same “weight” in the order of operations (meaning, you do them left-to-right).
Another commenter mentioned something similar, how they’re interchangeable, but I’m not sure why you say it’s fucking people over.
It should be limited - like Orders - to only Multiplication and Addition
Because you don’t want people to know when to do Division and Subtraction? 😂
Because division is the same operation as multiplication
No it isn’t, but they are both binary operators.
they have the same “weight” in the order of operations (meaning, you do them left-to-right)
And where are they going to do Division and Subtraction in the left to right if you’ve left them out? 🙄
Because you don’t want people to know when to do Division and Subtraction? 😂
Because division is multiplication, and subtraction is addition.
No it isn’t, but they are both binary operators.
2/2is the same as2*½2-2is the same as2+(-2)And where are they going to do Division and Subtraction in the left to right if you’ve left them out? 🙄
Well, as I already said multiple times: Division = Multiplication and Subtraction = Addition, therefore they would be doing them together, left to right. As in:
9-3+2would not confuse anyone who learned “Addition → Subtraction”, as it does right now.Because division is multiplication
No it isn’t.
and subtraction is addition
And you still have to do both
2/2 is the same as 2*½
They’re equal in value, they’re not the same
2-2 is the same as 2+(-2)
You got that the wrong way around. Brackets have only been used in Maths for a few centuries now
Well, as I already said multiple times: Division = Multiplication
And you were wrong every time you said it.
therefore they would be doing them together
Not if you left them out of the mnemonic and they didn’t know when to do them
Please Excuse My Dear Aunt Sally… bitches.
5 isn’t a valid function name, is obviously the right answer.
How can you be sure it’s not defined when we only see one line?
They didn’t say it’s not defined, they said it’s not a valid name. Most languages don’t allow function names to start with a number, so 5 literally cannot be a function if that’s the case.
But that’s assuming this isn’t some really obscure language.
so 5 literally cannot be a function if that’s the case
No, but it can be and is a coefficient of the Term 5(8-5)
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
Depends on the language.
Depends on the language
No it doesn’t
Yes it does.
Yes it does
Says person who can’t cite a single example of it depending on the language 🙄
2 5 8 5 - × + for you RPN fans =)
Pemdas, parenthesis first, for a total of 3. Then multiplication, 15, then addition. 17. What’s hard about this?
you go the other direction below the equator
What’s hard about it is people are fucking stupid.
No, it’s written poorly to drive engagement. People read left to right and try to do math that way too, but if you want to be mean to people who don’t remember things they learned in elementary school then never applied in real life you write it like OP.
(8-5)5+2
Far easier for most people, but then you don’t get the arguments…
It’s written the same way literally thousands of math problems in thousands of textbooks have written the same type of math problem for the last 100 years. OP did not write it that way to be “mean.” He wrote it that way because it’s a legit way to write it.
The operational order is fucked, the way I rewrote is more readable, even if you remember the order. The only reason you’d write the equation like that is to be mean, there’s no reason to write it like that unless you’re trying to trip people up.
The operational order is fucked
No it isn’t.
the way I rewrote is
Wrong.
The only reason you’d write the equation like that is
Because it’s written like that in Maths textbooks
there’s no reason to write it like that unless you’re
Obeying the rules of Maths, as found in Maths textbooks
You got it wrong on your first try, didn’t you? Lol, it’s not “mean” to write a math problem. The whole point of memorizing the order of operations is so that you can solve it no matter what order the equation is written in. No one wrote this problem on purpose just to make you fail to understand it, that’s dumb.
This was literally written for twitter content…
I just fail to see how you come to the conclusion that it was written in a “mean” way. It’s math, there is no “nice” way to write an equation.
No, it’s written poorly
No it isn’t
drive engagement
The engagement comes from people not remembering the rules of Maths
(8-5)5
That’s an invalid syntax. it’s 5(8-5) or 5x(8-5), nothing else. Why is it invalid? Imagine (8-5)-5 - am I multiplying what’s in the brackets by -5 (which gives -15), or subtracting 5 after doing the brackets (which gives -2)? Invalid syntax
Far easier for most people
Nope, it’s wrong for everyone, due to being an invalid syntax.
Yes, thank you! Sure, it’d be great if people remembered arithmetic rules, but just write it better and it won’t matter.
just write it better
It’s written like that in Maths textbooks. i.e. there’s nothing wrong with it.
I fucking suck at math and totally just re-proved it to myself with this problem lmao.
It didn’t make sense to me to multiply the 3 & the 5 with zero consideration for the “2”. I have ALWAYS struggled with the steps to solve these types of equations.
So the answer I got was 21. Some of us are just bad with numbers, I s’pose.
It didn’t make sense to me to multiply the 3 & the 5 with zero consideration for the “2”
That’s what the order of operations rules say to do. 2 doesn’t come into it until you get down to the Addition step.
Pemdas, parenthesis first, for a total of 3
Nope, a total of 15.
Then multiplication
There isn’t any Multiplication, only Addition and Brackets (and Subtraction inside Brackets).
You have to subtract the numbers with the most flat sides first and divide by the number of pennies in your sock drawer.
I’m not seeing a single mention of My Dear Aunt Sally. The youth are lost…
You’re drunk Sally, go to bedmas!
I’ll never understand these approaches to learning. They require remembering the phrase, and then require remembering how the phrase translates to the rules you need to remember.
I’ll just remember the rules in the first place. Less effort.
I’ll never understand these approaches to learning. They require remembering the phrase, and then require remembering how the phrase translates to the rules you need to remember
Yeah, exactly, but the U.S. seems to have a chip on it’s shoulder about always doing everything differently to the whole rest of the world. “Maths? We’re not going to use BEDMAS, and we’re not going to call them Brackets, and…”.
Was anyone else ever taught it as BOMDAS as opposed to BODMAS?
It was BEDMAS for us, where the E was exponents or something.
Found the Canadian
Found the Canadian
Nope, it’s the same in Australia and the U.K.
Sorry, found the Commonwealther
found the Commonwealther
Or more precisely, the non-USer 😜
Okay, sorry, found the person from a sane country 😂
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. 🙄
PEMDAS, is that the same as BOMDAS?
They’re all just different mnemonics for the same rules.
I think so. Amazing how many different ways there are to say it
So instead of Parentheses, Exponents is it Box and O that digit in the sky?
Brackets and Orders, not that anybody calls “(” a bracket or “^” an “order”.
Brackets and Orders, not that anybody calls “(” a bracket or “^” an “order”.
It’s “to the order of” actually. 2² is 2 to the order of 2
not that anybody calls “(” a bracket
Yes we do. They’re ALL Brackets - square, round, squiggly…
Why do people put bot pairs of multiplication and division, and addition and subtraction on the acronym?
Do you really follow that order with the associative operations?
Why do people put bot pairs of multiplication and division, and addition and subtraction on the acronym?
Because it’s intended to be used as a checklist
Do you really follow that order with the associative operations?
Yep
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
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
Its because its:
2+5×(8−5)
My calculator app automatically added it when typing in what was in the image and “2+5×(8−5)” does equal 17.
It’s absolutely the fault of the person making the social media media post for not writing it properly and confusing people.
Its because its: 2+5×(8−5)
No it isn’t. It’s 2+5(8−5). Different expression, but in this case co-incidentally the same answer. Preface the first 5 with a Division and you get different answers.
My calculator app
Was written by a programmer who didn’t check the rules of Maths first. The only e-calc I’ve ever seen give the correct answer is MathGPT
not writing it properly
Except it is written properly, as per Maths textbooks
What du you mean, not writing it properly?
What du you mean, not writing it properly?
They mean they don’t remember being taught that is the correct way to write it
The multiplication is implied and has been part of the standard mathematical notation for far longer than any of us have been alive.
The multiplication is implied
No it’s not. It’s explicitly The Distributive Law, a(b+c)=(ab+ac). There is no Multiplication
5(8-5) is perfectly fine, it’s like saying 5 apples
it’s like saying 5 apples
5 baskets each with 3 apples actually
I mean yeah, in my example apple = 3
I have some bad news for you about your education system
I have some bad news for you about your education system
It’s not the Education system, it’s people not remembering what they were taught
OMG! That’s the first time I’ve actually seen AI get order of operations right! 😂
are you THAT lazy
Fuck everyone else I thought this was funny
So you’re the guy that asked chat GPT if you could enter Chile without a passport, said yes, come to Chile and had to go back because you actually needed a passport huh?.
It surprises me the amount of people who just “outsource” their intelligence to a fking chatbot and then proceed their way in life taking moronic decisions all over, a reminder AI companies depend on people being too lazy to think to be able to sell their products.
Coal rolling, but for IT-literate.
Funny, tell that to the billionaires who have a private jet.
I am. I’m also telling you.
Or it simply could be that I haven’t needed to concern myself with the order of operations more than a dozen times since high school. Even when working as a web coder it was so seldom necessary that I can’t recall a single example.
The US education system was still pretty decent when I was in middle and high school in the 1980s, so we definitely covered this in algebra.
I haven’t had to do this shit in 20 years since college. Literally nothing like this in my career path, I was shit at math in high school and college, so I didn’t even remember that there was a multiplication there since it isn’t explicit. Oh well.
that there was a multiplication there since it isn’t explicit
There isn’t a Multiplication there, only Addition and Brackets, and Subtraction inside Brackets. It’s never Multiplication unless there is a Multiplication sign.
Good for you. I don’t care.
Let’s not do engagement bait here 😭
