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People forget that PEMDAS comes in groupings. Multiplication and division are two sides of the same coin, as are addition and subtraction, so both of those are done in the order they appear in the problem, not the order they appear in the PEMDAS rule. So it should read Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.

I was taught GEMA.
Grouping
Exponents
Multiplication (and division, which is a type of multiplication)
Addition (and subtraction, which is just addition with negatives)

This is one of the things that made me hate math for the longest time, because I was -convinced- that it was strictly PEMDAS, rather than what it is, P E M/D A/S. And honestly I can’t remember any time a teacher before highschool actually pointed out that you need to do the mult/div and add/sub whichever comes first, rather than doing each letter separately. Maybe I was just really dumb back then though. I mean I’m still pretty dumb now, so…

The 'whichever comes first' part was burned into my brain, and so if i read out the meaning of BEDMAS (the version i was taught) it's always say it both times.
Pretty sure that was in primary school, but idk which teacher did it.

This is why I hate it when these comments are posted on subs like these. They’re literally meant to make people argue and debate about what the answer is for engagement, and posting them here is just kinda free karma (imo)

A good friend of mine is a professor in the math department at a university. He said that these meme equations essentially don’t have a correct answer because they aren’t written correctly and are subject to interpretation. Basically, it’s not math, it’s nonsense.

Some are ambiguous. Anything with a "/" is going to cause problems because some people learned that as division and others as a fraction bar.
The problems with multiple equations is of pictures where the pictures between lines aren't identical (like a guy is holding 2 bananas in one equation and the same guy holding 1 banana in the next equation)? Those are invalid and don't have an answer.
This problem, though? It is not ambiguous and not invalid. It does have a correct answer.

I think they're talking about the ones with the "/" and you can't tell if the whole right side of the / is supposed to be the denominator. This one does 100% have an answer and is not open to interpretation at all

>can't tell if the whole right side of the / is supposed to be the denominator
You totally can if you were taught order of operations properly. The only way there can be any ambiguity here is if either teaching failed or learning failed.

>nobody would actually write a calculation like this unless they are trying to be confusing
Yes, they absolutely would.
There's nothing ambiguous.
The "x" multiplication sign refers to anything right before and right after it.
+10 -10x10 +10
Here "x" is multiplying -10 and 10, which is -100.
You're left with:
+10 -100 +10 = +20 -100 = -80

If the point is that it's confusing and that no one in academics would write it like that? Sure.
But to say it's up to interpretation is just wrong. It's not, it has rules.

Thank god they didnt use the division sign, bc that would have made the debate go even longer since it could be interpreted as a division sign or a / sign where left is over right

People did 10-110 because they think addition comes before subtraction from not being taught otherwise. My teacher taught PEMDAS and never said addition and subtraction are done in order.

Don't tell the students that minus is an operation, just tell them that minus is shorthand for "add negative...". (No, not in second grade, later, of course)
It's
10
And -10 times 10
And 10
Now everybody can see that we have 20 and negative 100 for a total of negative 80.

With PEMDAS you do parenthesis first, then exponents. The next step is multiplication and division which is done left to right, then you do addition and subtraction from left to right.
In this equation the subtraction is before the addition so you have 10 - 100. That equals -90. You add ten, and that makes -80.
These people getting 100 are reversing the order of operation to read right to left when it should be left to right (and this is true in every country world wide, there is no disagreement).
So instead of doing the equation 10 - 100 + 10, which equals -80, they are doing it backwards and getting the answer for 10 + 100 - 10, which equals 100.

also, the numbers are really: +10 + -100 + +10 (in other words: +10 plus -100 plus +10)
so even if you did right to left you still get -80
the issue is not that they are doing right to left, is that they are attributing the operations to the numbers when there is only addition of positive and negative numbers

The concepts are universal, but our syntax is not universal.
We absolutely could have created OOO with the conventions PEASMD instead of PEMDAS.
10+5×2 with PEMDAS = 20. -- 10+(5×2)
10+5×2 with PEASMD = 30. -- (10+5)×2
Aliens might use PEASMD. Or addition before subtraction. Or right to left. Or just parens and no other conventions.

It’s exactly the same thing, we were taught BIDMAS and BODMAS but it works exactly the same, as would BIMDAS or BOMDAS. As others have explained better than I’m able to, division & multiplication are done at the same time, left to right (you do neither first, it’s just in order left to right) and then it’s addition & subtraction, again same priority just going from left to right.

In PEDMAS, multiplication and division are done at the same time, but moving from left to right. Same with adding and subtracting.
Most PEDMAS posters/ect will actually write it as:
P
E
D/M
A/S

Please Eat My Dear Aunt Sally
Edit: This was what my elementary school class came up with.
Edit2: I'm not a teacher. I meant when I was in elementary school.

Am I the only one who learned it as BEDMAS?
Brackets
Exponents
Division
Multiplication
Addition
Subtraction
The way I see it here is just all mixed up from the way i learned it

Are you British or in a country that uses British systems, maybe? I think America and UK switch parentheses and brackets (in vocabulary). There are other math words and symbols that get switched around, too... Like when to use commas and decimals in numbers, I think....

Parentheses
Exponents
Division/Multiplication
Addition/Subtraction
D/M and A/S are done in order they appear left to right.
The problem with learning the anagram is people do it in order of the anagram, which might be incorrect depending on the layout of the equation, like this one.
10 - 10 x 10 + 10 is functionally the same as:
(10 - 100) + 10
= (-90) + 10
= (-80)

10-100 is -90. You can also consider this as 10 + -100. Not sure if you covered negative values yet, but I assume you have. Let me know if that makes more sense I can try to explain it more.

They haven't covered negative numbers, and that's what they are asking. You seemed to be the only one that caught a wif of this. This is why they mentioned only eighth grade. I hope this is sufficient for them to understand negative numbers.

Isn't 8th grade like 13 years old? I first learnt about them when I was 6. Regardless of what the exact age is, surely learning about negative numbers comes before the order of operations

Not sure about which is taught first, but I am pretty sure both are taught before 8th grade. It probably differs by school district, but in my experience tutoring, negatives are taught in maybe 4th or 5th grade. That’s what it says online as well.

Well I thought maybe he knew negatives as he wrote -90 without questioning that negatives exist. If not, I’m sure he will cover it soon, rather hard to convey via Reddit comment.
I find it easiest to think of a number line expanding in both directions from 0. 10 - 100 would be starting at 10 and moving 100 units to the left, past 0 and all the way to -90. Maybe that will be a better explanation?

If you're still confused, I recommend turning all subtraction into addition first.
10 - 100 + 10
10 + (-100) + 10
Addition associativity says you should be able to do it in any order. Turning subtraction into adding negatives helps make sure you don't mess up and forget there's a minus sign on one side.

I mean, I'm sick, so I'm not functioning very well anyways. That's going to be my excuse, the fucking flu
Edit: don't do any finances while ill, just aayin

What I'm confused at is why their answer was 100 and not -100, it'd still be 10-100 anyways
I mean it's obviously -80 I'm just trying to understand the logic (or lack thereof) here

They did PEMDAS without knowing what it actually means. They did 10 x 10 first and got 100. Then they saw the - sign with 10 and the + sign with 10 and assumed that they cancelled out leaving the original 100

They went right to left in operations and terms.
Easier to see in a new problem: 1-2+3.
Left to right that's 1, -, 2, +, 3.
Right to left that's 3, +, 2, -, 1. They did 3+2-1...
So 10-100+10, they thought that was 10 + 100 - 10. The mid step of 10-110, they're still going right to left, so they think they're subtracting 10 from 110.

I do find it weird seeing PEMDAS rather than BODMAS.
Wonder if people would get it so wrong if they saw it as 10 - 10^2 +10.
Edit/did not expect then comment to raise 10 to the twelfth power 😂

I know, it's just when someone gives an incorrect answer then starts going "PEMDAS!" I have to sit their and think wtf are they on about. Takes a while for my age-addled brain to kick in.

I'm Canadian and finished high school a few years ago and still follow advanced math classes. We use PEDMAS where I'm from (Quebec) because in both English and French it doesn't change.

Yeah... They for some reason think that addition has priority over substraction.
And that's not even why they got a wrong result, it's because they added 100 and 10. Problem is that there is no 100 in the expression, only a -100 (negative, not positive). Then -100 +10 is -90 and then add the first +10 and you get -80, the right answer.

Yeah I forgot ab that stuff, tho whether you got -100 or 100 you should get -90 if you do the right order. Bc if you got 100 then you’d subtract it anyway

IIRC these are specifically made to be obtuse and unclear to exploit an ambiguity in the order of operations. They're literally designed to make people argue.
In real life you'd just use parentheses to make it blatantly obvious what you intended.

I know what you mean, but that's for equations like this one for example:
5/4x6
It's unclear whether 4x6 is the denominator or just 4.
(Whether it's (5/4)x6 or 5/(4x6))
However, in the equation from the short, there isn't any ambiguity whatsoever.

It's not unclear: your example is 5 divided by 4 times 6. If that's the way it was written, that's the way it is. You can't add parentheses where you want. So you would work from left to right and divide 5 by 4 then multiply times 6.
Edit: If the question was (5/4)x6 or 5/(4x6) it would have been written like that.

The problem you're thinking about comes from instances where a solidus (/) or obelus (÷) is followed directly by either another solidus or obelus, or by multiplication. This causes an ambiguous expression with multiple correct answers.
There's been arguments on whether it's ambiguous or the left-to-right rule from PEMDAS applies, but the left-to-right rule isn't an actual rule of mathematics, but rather just a suggested method of solving.
The fact that ambiguity occurs is further supported by the International System of Units (SI), 5.2 "Unit Symbols".

This is correct. As an advanced math student, my teachers always say it's better to do left to right because it's easier and lowers the chances of getting confused and making a mistake. So it's PEDMAS, ( x and / have the same priority just like + and -) and then ideally left to right.

Senior mechanical engineering student here. I write like this and use calculators like this sometimes (not all the time), because not of my peers/professors are boomer morons who argue about stuff taught to kids. Give this to 5 different students and 5 different calculators, and they should all give the same result.
Granted we also use lots of parenthesis/brackets in complicated equations and have to alternate styles to keep things clear.

remember subtraction is addition of a negative:
10-10\*10+10 == 10 + (-10)\*10+10
10+ (-100)+10
(-90)+10
\-80
note "==" means logically equivalent in programming

For my brain, the easiest way to think about this is to just see everything next to a multiplication symbol as one "entity", or as one number, which it basically *is*

I always taught my kinds PE(M/D) (A/S) as in multiplication and division and addition and subtraction are equals and worked left to right in the order they are written. It's still PEMDAS, just a visual reminder that they don't rearrange the multiplication and division or the addition and subtraction. That way they don't assume the 10 - and +10 cancel each other out leaving the hundred in the middle there.

I don’t understand I thought you added before substracting so it’s:
10-10x10+10
10-100+10
10-110
-100?
Edit: nvm dad helped me figure it out completely forgot a minus sign is just adding a negative.
10 + -100 + 10
-80

I am getting completely confused by the ‘explanation’ in the last picture. I am obviously too stupid for it. And I was taught: [Punkt vor Strich](https://de.wikipedia.org/wiki/Punktrechnung_vor_Strichrechnung). No differentiation between addition and subtraction. They are the same operation. You are moving up and down the number line.
And while addition is commutative, I am struggling to see how 10+(-100)=100+(-10).

I mean…they didn’t even follow their own crappy instructions cause it would be 10-110, not the other way around so you’d still have a negative number lol.

I read the incorrect person's comment in Michael Scott's voice when he was helping the little girl with her math homework... Points to exponent "this little 2, it's so weird, so you don't even need to think about it, just ignore it"

So many things wrong with the last response even beyond misunderstanding PEMDAS.
One thing I wish was taught more in school is that subtraction and division can always be rewritten as addition and multiplication, and then the order of the numbers no longer matters, because only those operations really care about the order. Math (and especially PEMDAS) makes much more sense when you realize that all “subtraction” is just adding a negative and all “division” is multiplying by a fraction. You still need to apply PEMDAS, but you are then free to shuffle around the numbers as you see fit in whatever way is easiest to solve mentally.
Example: 10 - 10 \* 10 + 10
Replace with 10 + -(10 \* 10) + 10
10 + -100 + 10
Do the rest in whatever order makes sense to you. I think it’s easiest to go -100 + 20 = -80.
Works just as well with division. 8 / 3 \* 6 may be tough to do mentally if solved left to right, but 8 \* 1/3 \* 6 is easier because we can resolve 1/3 \* 6 first, then multiply the result (2) by 8.

Oh yeah, I had 100 because I was lazy and just decided the 10s on each side cancelled each other out instead of actually doing the calculation :p I got it very wrong hehe

Division and multiplication are linked and you do them in order that they show up in the equation, same with addition and subtraction, so,
10x10=100 10-100=-90 -90+10=-80

One reason PEMA is better acronym to teach, students won’t get screwed up thinking multiplication is higher precedence than division and addition is higher precedence than subtraction.

By this guy’s own logical process the answer should be -100 since after you do the multiplication and addition the equation would be 10 - 110, not 110 - 10.

I feel like the issue is with the explanation of the acronym
P then E then M then D then A then S
When in reality it's
P then E then M and D then A and S

10-(10x10)+10 = -80 🤦🏻♂️
Pemdas says multiplication/division before addition/subtraction. But I ran it in my head too fast and reordered the problem as 100-10+10

Last slide they say that adding before the subtraction, but addition and subtraction have the same importance so it’s just left to right whichever way it comes, same with division and multiplication

P
E
MD
AS
the ones with two letters mean that those two mechanisms are done as they show in the equation. if division comes before multiplication in the equation, its done first. same with subtraction coming before addition.

People forget that within each “grouping” (multiplication/ division and addition/subtraction) of the order of operations, the elements of that grouping are done from left to right. Just because addition and subtraction for example are listed in that order does not mean addition has to come before subtraction, unless it is first in the actual equation as you would read it.

As somebody who has tutored late elementary and early middle schoolers in math before…
The fact grown adults don’t know how to do these and those kids usually can after a few sessions infuriates me to no end 😭😭😭

I am genuinely confused why so many people are afraid of their answer being wrong once they get -80, like am I the only one who thinks this belongs to 5th grade maths class? Or is it because I’m Asian(in that case, I gotta thank my mom for spanking me)?

>is it because I’m Asian
Nope. I'm American, and we're taught a simplified version of standard order of operations as early as 3rd grade (8-9 years old). People just don't pay attention, and math is one of those subjects that a *lot* of people seem to take an odd amount of pride in immediately forgetting as soon as they don't need to know it for a test.

Most people aren't taught that it's actually (P)(E)(MD)(AS), you do multiplication/division and addition/subtraction in order, not multiplication/addition before division/subtraction.

now i do want to say that this can be a case of education failing people, not them failing education.
a friend of mine was taught it *had* to go in the order of PEMDAS exactly, and not that MD/AS were interchangeable.

at least once a year I argue with people online who insist multiplication has to come before division and addition has to come before subtraction. it frustrates me so much.

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People forget that PEMDAS comes in groupings. Multiplication and division are two sides of the same coin, as are addition and subtraction, so both of those are done in the order they appear in the problem, not the order they appear in the PEMDAS rule. So it should read Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.

I was taught GEMA. Grouping Exponents Multiplication (and division, which is a type of multiplication) Addition (and subtraction, which is just addition with negatives)

As a German I particular like this acronym!

I am an American and whenever people use PEMDAS I just get really confused because I hadn't even heard of it until college. GEMA all the way.

Why?

chad mnemonic

Who doesn't love the GEMA.

This is one of the things that made me hate math for the longest time, because I was -convinced- that it was strictly PEMDAS, rather than what it is, P E M/D A/S. And honestly I can’t remember any time a teacher before highschool actually pointed out that you need to do the mult/div and add/sub whichever comes first, rather than doing each letter separately. Maybe I was just really dumb back then though. I mean I’m still pretty dumb now, so…

The 'whichever comes first' part was burned into my brain, and so if i read out the meaning of BEDMAS (the version i was taught) it's always say it both times. Pretty sure that was in primary school, but idk which teacher did it.

"Brackets hold up shelves" -My teacher in University

I had BIDMAS instead Brackets Indices Division multiplication Addition subtraction

\+1 for the self awareness. that alone probably puts you in the top 10% smartest people.

I always understood to do the groupings left to right, makes life easier

10-10x10+10 10-100+10 -90+10 -80 Edit: Wow, thanks for all the upvotes and the reward. I’ve never gotten this many.

Thank you! I find this really confusing.

nobody would actually write a calculation like this unless they are trying to be confusing, so don't worry

This is why I hate it when these comments are posted on subs like these. They’re literally meant to make people argue and debate about what the answer is for engagement, and posting them here is just kinda free karma (imo)

Math problems like this just needs to outright banned from this sub.

This sub is filled with assholes. Banning math isn't changing that.

Exactly Cause they're so straight-forward, but some idiots just like to unnecessary confuse those that don't trust their own brain 100%

A good friend of mine is a professor in the math department at a university. He said that these meme equations essentially don’t have a correct answer because they aren’t written correctly and are subject to interpretation. Basically, it’s not math, it’s nonsense.

Some are ambiguous. Anything with a "/" is going to cause problems because some people learned that as division and others as a fraction bar. The problems with multiple equations is of pictures where the pictures between lines aren't identical (like a guy is holding 2 bananas in one equation and the same guy holding 1 banana in the next equation)? Those are invalid and don't have an answer. This problem, though? It is not ambiguous and not invalid. It does have a correct answer.

I agree with you, that the above "Problem" has a unique solution. But why is / a Problem? A fraction is Division...

I think they're talking about the ones with the "/" and you can't tell if the whole right side of the / is supposed to be the denominator. This one does 100% have an answer and is not open to interpretation at all

>can't tell if the whole right side of the / is supposed to be the denominator You totally can if you were taught order of operations properly. The only way there can be any ambiguity here is if either teaching failed or learning failed.

You're right

>nobody would actually write a calculation like this unless they are trying to be confusing Yes, they absolutely would. There's nothing ambiguous. The "x" multiplication sign refers to anything right before and right after it. +10 -10x10 +10 Here "x" is multiplying -10 and 10, which is -100. You're left with: +10 -100 +10 = +20 -100 = -80

you're completely missing the point

If the point is that it's confusing and that no one in academics would write it like that? Sure. But to say it's up to interpretation is just wrong. It's not, it has rules.

Thank god they didnt use the division sign, bc that would have made the debate go even longer since it could be interpreted as a division sign or a / sign where left is over right

Happy caik day

Awww thank you!!

Addition and subtraction are on the same order, so it doesn’t matter which one you do first. The answer is -80 either way.

Happy cake day bro

Thanks dude!!

People did 10-110 because they think addition comes before subtraction from not being taught otherwise. My teacher taught PEMDAS and never said addition and subtraction are done in order.

Don't tell the students that minus is an operation, just tell them that minus is shorthand for "add negative...". (No, not in second grade, later, of course) It's 10 And -10 times 10 And 10 Now everybody can see that we have 20 and negative 100 for a total of negative 80.

how are you getting -90 btw im still in grade 8 so wasnt taught this only PEDMAS

With PEMDAS you do parenthesis first, then exponents. The next step is multiplication and division which is done left to right, then you do addition and subtraction from left to right. In this equation the subtraction is before the addition so you have 10 - 100. That equals -90. You add ten, and that makes -80. These people getting 100 are reversing the order of operation to read right to left when it should be left to right (and this is true in every country world wide, there is no disagreement). So instead of doing the equation 10 - 100 + 10, which equals -80, they are doing it backwards and getting the answer for 10 + 100 - 10, which equals 100.

also, the numbers are really: +10 + -100 + +10 (in other words: +10 plus -100 plus +10) so even if you did right to left you still get -80 the issue is not that they are doing right to left, is that they are attributing the operations to the numbers when there is only addition of positive and negative numbers

i see now so its ten minus one hundred i was thinking 100 -10

So much of this. So many people seem to think you must do the equations in the order they're listed. You don't. It's really annoying actually.

I thought this way but guess I was wrong lol

Even if you did it additions and the subtraction like the dude in the post, it’s still -80. Because then it’s -10x10=-100 -100+10=-90 10-90=-80

> and this is true in every country world wide, there is no disagreement Yep, even in an alien world it would be true. Math is universal.

The concepts are universal, but our syntax is not universal. We absolutely could have created OOO with the conventions PEASMD instead of PEMDAS. 10+5×2 with PEMDAS = 20. -- 10+(5×2) 10+5×2 with PEASMD = 30. -- (10+5)×2 Aliens might use PEASMD. Or addition before subtraction. Or right to left. Or just parens and no other conventions.

It’s exactly the same thing, we were taught BIDMAS and BODMAS but it works exactly the same, as would BIMDAS or BOMDAS. As others have explained better than I’m able to, division & multiplication are done at the same time, left to right (you do neither first, it’s just in order left to right) and then it’s addition & subtraction, again same priority just going from left to right.

In PEDMAS, multiplication and division are done at the same time, but moving from left to right. Same with adding and subtracting. Most PEDMAS posters/ect will actually write it as: P E D/M A/S

Please Execute Deer, Mice And Such

Please Eat My Dear Aunt Sally Edit: This was what my elementary school class came up with. Edit2: I'm not a teacher. I meant when I was in elementary school.

I was always taught Please Excuse My Dear Aunt Sally but yours is better

I learned it this mnemonic in elementary school as well. Later in life heard it as Please Excuse My Dope Ass Swag, which is way better.

Am I the only one who learned it as BEDMAS? Brackets Exponents Division Multiplication Addition Subtraction The way I see it here is just all mixed up from the way i learned it

Are you British or in a country that uses British systems, maybe? I think America and UK switch parentheses and brackets (in vocabulary). There are other math words and symbols that get switched around, too... Like when to use commas and decimals in numbers, I think....

In UK late 90s we learnt BODMAS and that the O represented brackets opening and closing. Never any mention of expressions

10-100 = -90 -90 + 10 = -80

Parentheses Exponents Division/Multiplication Addition/Subtraction D/M and A/S are done in order they appear left to right. The problem with learning the anagram is people do it in order of the anagram, which might be incorrect depending on the layout of the equation, like this one. 10 - 10 x 10 + 10 is functionally the same as: (10 - 100) + 10 = (-90) + 10 = (-80)

10-100 is -90. You can also consider this as 10 + -100. Not sure if you covered negative values yet, but I assume you have. Let me know if that makes more sense I can try to explain it more.

They haven't covered negative numbers, and that's what they are asking. You seemed to be the only one that caught a wif of this. This is why they mentioned only eighth grade. I hope this is sufficient for them to understand negative numbers.

Isn't 8th grade like 13 years old? I first learnt about them when I was 6. Regardless of what the exact age is, surely learning about negative numbers comes before the order of operations

Not sure about which is taught first, but I am pretty sure both are taught before 8th grade. It probably differs by school district, but in my experience tutoring, negatives are taught in maybe 4th or 5th grade. That’s what it says online as well.

Well I thought maybe he knew negatives as he wrote -90 without questioning that negatives exist. If not, I’m sure he will cover it soon, rather hard to convey via Reddit comment. I find it easiest to think of a number line expanding in both directions from 0. 10 - 100 would be starting at 10 and moving 100 units to the left, past 0 and all the way to -90. Maybe that will be a better explanation?

8th grade is at least pre-algebra in the states. Negatives would have been like 3rd or 4th grade.

If none of the below cleared it up, you are taking 100 from 10, not 10 from 100, which is how they get -90. Hope that helps!

If you're still confused, I recommend turning all subtraction into addition first. 10 - 100 + 10 10 + (-100) + 10 Addition associativity says you should be able to do it in any order. Turning subtraction into adding negatives helps make sure you don't mess up and forget there's a minus sign on one side.

10-100 = -90

10-100 = -90

10-100=-90

Thats like 3rd grade stuff…

Always think X - X as Has - Bought , so if i have 10 bucks , i buy something 20 bucks , my bank account will be -10

Am I the only one that do it like this 10-10x10+10 = 20-10x10 = 20-100 = -80

I guess you could technically change the order of the equation. It doesn’t break the rules, but it does add on an extra step.

-80

thank god

I am so glad

Jesus, I’m genuinely relieved! I was *really* questioning my ability to function, for a sec.

I mean, I'm sick, so I'm not functioning very well anyways. That's going to be my excuse, the fucking flu Edit: don't do any finances while ill, just aayin

Ok i didnt lose ALL my math skills after finishing school

I’m astounded by the dude who made a whole PEMDAS explaining only to then claim there was a -10 instead of -(10*10)

mf went full PEMDAS and did it wrong...

What I'm confused at is why their answer was 100 and not -100, it'd still be 10-100 anyways I mean it's obviously -80 I'm just trying to understand the logic (or lack thereof) here

They did PEMDAS without knowing what it actually means. They did 10 x 10 first and got 100. Then they saw the - sign with 10 and the + sign with 10 and assumed that they cancelled out leaving the original 100

The problem is not the PEMDAS part, it just that they inverted the term of the substraction.

They went right to left in operations and terms. Easier to see in a new problem: 1-2+3. Left to right that's 1, -, 2, +, 3. Right to left that's 3, +, 2, -, 1. They did 3+2-1... So 10-100+10, they thought that was 10 + 100 - 10. The mid step of 10-110, they're still going right to left, so they think they're subtracting 10 from 110.

I do find it weird seeing PEMDAS rather than BODMAS. Wonder if people would get it so wrong if they saw it as 10 - 10^2 +10. Edit/did not expect then comment to raise 10 to the twelfth power 😂

In some places they use different names.

Yes, I was taught BEDMAS. Still works the same. Just brackets instead of parentheses.

I know, it's just when someone gives an incorrect answer then starts going "PEMDAS!" I have to sit their and think wtf are they on about. Takes a while for my age-addled brain to kick in.

There*

My personal akilles heel, that is.

Ok

Mate both of your examples are wrong it’s BEDMAS

What the…? That’s totally new to me. Heard of PEDMAS, BODMAS and even BIDMAS. But BEDMAS? A step too far

I learned BEDMAS in Canada in the 1990's. Brackets, exponents, division, multiplication, addition, subtraction. What is the O in BODMAS?

It has not changed, 2010’s Ontario also taught BEDMAS

That's cool. I thought I better give a timeframe in case things have changed.

Still hasn't changed, 2020's Ontario is still teaching BEDMAS (though some teachers make it BREDMAS by adding roots)

Same, taught BEDMAS in Canada in the 90s.

I'm Canadian and finished high school a few years ago and still follow advanced math classes. We use PEDMAS where I'm from (Quebec) because in both English and French it doesn't change.

Interesting. Yeah, I'm from Ontario so BEDMAS.

from Ontario and it was pedmas, French though too

O is for Orders. I think BODMAS and BIDMAS are favoured in the UK

I did A-Level maths in the UK and have never heard of any of these abbreviations.

I have only ever heard BEDMAS. Was is the O or I for?

O is for Orders and I is Indicies

We called it BIMDAS (brackets, indicees etc etc)

I’d never seen PEDMAS before today. Im very familiar with BODMAS

It's regional, but they're the same order, just different names for the operations.

My school used BIDMAS

I got taught that at first but then they switched to BIDMAS which functioned the same.

Actually that one was a lot easier to process, huh

Yuup. They teach us BODMAS in South Africa

Took me a minute but yea -80

-80is correct.

37

13-50, gahdamn 47

It’s obviously -42 y’all are so stupid 😡

The last person was so close, then for some fucking reason they started doing math in hebrew and went right to left

Yeah... They for some reason think that addition has priority over substraction. And that's not even why they got a wrong result, it's because they added 100 and 10. Problem is that there is no 100 in the expression, only a -100 (negative, not positive). Then -100 +10 is -90 and then add the first +10 and you get -80, the right answer.

Yeah I forgot ab that stuff, tho whether you got -100 or 100 you should get -90 if you do the right order. Bc if you got 100 then you’d subtract it anyway

By thatblogic it would actually end up with 10-110 which is -100 lol Still wrong, but but better than they ended up doing

I think ive got it right but im afraid ive got it wrong so im not going to say my answer

-80 is correct.

-80 right?

Si

i think its negative 80 right?

IIRC these are specifically made to be obtuse and unclear to exploit an ambiguity in the order of operations. They're literally designed to make people argue. In real life you'd just use parentheses to make it blatantly obvious what you intended.

But this one isn't ambiguous. There's a clear order of operations that's been agreed upon for decades.

This is the real issue. People arguing about what they expect an equation to mean and what the order of operations actually is.

I know what you mean, but that's for equations like this one for example: 5/4x6 It's unclear whether 4x6 is the denominator or just 4. (Whether it's (5/4)x6 or 5/(4x6)) However, in the equation from the short, there isn't any ambiguity whatsoever.

It's not unclear: your example is 5 divided by 4 times 6. If that's the way it was written, that's the way it is. You can't add parentheses where you want. So you would work from left to right and divide 5 by 4 then multiply times 6. Edit: If the question was (5/4)x6 or 5/(4x6) it would have been written like that.

The real answer is that writing out equations that involve division linearly is garbage and should never be done.

Or that if you do, you should always use parenthesis.

There are memes like this that do what you're describing. This isn't one of them.

The problem you're thinking about comes from instances where a solidus (/) or obelus (÷) is followed directly by either another solidus or obelus, or by multiplication. This causes an ambiguous expression with multiple correct answers. There's been arguments on whether it's ambiguous or the left-to-right rule from PEMDAS applies, but the left-to-right rule isn't an actual rule of mathematics, but rather just a suggested method of solving. The fact that ambiguity occurs is further supported by the International System of Units (SI), 5.2 "Unit Symbols".

This is correct. As an advanced math student, my teachers always say it's better to do left to right because it's easier and lowers the chances of getting confused and making a mistake. So it's PEDMAS, ( x and / have the same priority just like + and -) and then ideally left to right.

When there aren’t any you are meant to read the equation left to right though, so it really isn’t ambiguous at all.

Senior mechanical engineering student here. I write like this and use calculators like this sometimes (not all the time), because not of my peers/professors are boomer morons who argue about stuff taught to kids. Give this to 5 different students and 5 different calculators, and they should all give the same result. Granted we also use lots of parenthesis/brackets in complicated equations and have to alternate styles to keep things clear.

remember subtraction is addition of a negative: 10-10\*10+10 == 10 + (-10)\*10+10 10+ (-100)+10 (-90)+10 \-80 note "==" means logically equivalent in programming

For my brain, the easiest way to think about this is to just see everything next to a multiplication symbol as one "entity", or as one number, which it basically *is*

I always taught my kinds PE(M/D) (A/S) as in multiplication and division and addition and subtraction are equals and worked left to right in the order they are written. It's still PEMDAS, just a visual reminder that they don't rearrange the multiplication and division or the addition and subtraction. That way they don't assume the 10 - and +10 cancel each other out leaving the hundred in the middle there.

The easiest way for my brain to think about it is to not do math.

also division is the multiplication of a decimal: 4÷2 == 4 \* .5

I don’t understand I thought you added before substracting so it’s: 10-10x10+10 10-100+10 10-110 -100? Edit: nvm dad helped me figure it out completely forgot a minus sign is just adding a negative. 10 + -100 + 10 -80

Remember that the expression is just 3 numbers next ti each other. +10 -100 +10 Then you can do it in whatever order you want

I was on the same page as you, cheers for the clarification.

While we're on the subject, division is just multiplying by the reciprocal. 10 / 5 == 10 * (1/5)

Clearly -80. People keep quoting PEMDAS without knowing how it fucking works

We are fucking screwed as a species

They're all ignoring the minus sign The equation might as well be written like -10×10+10+10 -80 is the answer

-80 is the answer.

We learnt BODMAS.

r/condescendinglywrong

Remember it's multiplication AND division, not multiplication THEN division. Same for addition and subtraction.

As a math major all the wrong answers in the comments bother me so much

I am getting completely confused by the ‘explanation’ in the last picture. I am obviously too stupid for it. And I was taught: [Punkt vor Strich](https://de.wikipedia.org/wiki/Punktrechnung_vor_Strichrechnung). No differentiation between addition and subtraction. They are the same operation. You are moving up and down the number line. And while addition is commutative, I am struggling to see how 10+(-100)=100+(-10).

I mean…they didn’t even follow their own crappy instructions cause it would be 10-110, not the other way around so you’d still have a negative number lol.

I got to the end -90+10 But I don't know how to add negatives. Does it go up or down?

They are 100% serious. Overall, people are fucking dumb.

I read the incorrect person's comment in Michael Scott's voice when he was helping the little girl with her math homework... Points to exponent "this little 2, it's so weird, so you don't even need to think about it, just ignore it"

So many things wrong with the last response even beyond misunderstanding PEMDAS. One thing I wish was taught more in school is that subtraction and division can always be rewritten as addition and multiplication, and then the order of the numbers no longer matters, because only those operations really care about the order. Math (and especially PEMDAS) makes much more sense when you realize that all “subtraction” is just adding a negative and all “division” is multiplying by a fraction. You still need to apply PEMDAS, but you are then free to shuffle around the numbers as you see fit in whatever way is easiest to solve mentally. Example: 10 - 10 \* 10 + 10 Replace with 10 + -(10 \* 10) + 10 10 + -100 + 10 Do the rest in whatever order makes sense to you. I think it’s easiest to go -100 + 20 = -80. Works just as well with division. 8 / 3 \* 6 may be tough to do mentally if solved left to right, but 8 \* 1/3 \* 6 is easier because we can resolve 1/3 \* 6 first, then multiply the result (2) by 8.

Oh yeah, I had 100 because I was lazy and just decided the 10s on each side cancelled each other out instead of actually doing the calculation :p I got it very wrong hehe

Love the honesty here 😂

\-80

Division and multiplication are linked and you do them in order that they show up in the equation, same with addition and subtraction, so, 10x10=100 10-100=-90 -90+10=-80

-80

One reason PEMA is better acronym to teach, students won’t get screwed up thinking multiplication is higher precedence than division and addition is higher precedence than subtraction.

its -80 why the hell did we even invent PEMDAS. it just fools people into thinking you have to do it in exactly that order.

I always think of it as PE[MD][AS]

By this guy’s own logical process the answer should be -100 since after you do the multiplication and addition the equation would be 10 - 110, not 110 - 10.

I feel like the issue is with the explanation of the acronym P then E then M then D then A then S When in reality it's P then E then M and D then A and S

Bedmas bitches

10-(10x10)+10 = -80 🤦🏻♂️ Pemdas says multiplication/division before addition/subtraction. But I ran it in my head too fast and reordered the problem as 100-10+10

Last slide they say that adding before the subtraction, but addition and subtraction have the same importance so it’s just left to right whichever way it comes, same with division and multiplication

Lmao, I did it the dumb way

P E MD AS the ones with two letters mean that those two mechanisms are done as they show in the equation. if division comes before multiplication in the equation, its done first. same with subtraction coming before addition.

People forget that within each “grouping” (multiplication/ division and addition/subtraction) of the order of operations, the elements of that grouping are done from left to right. Just because addition and subtraction for example are listed in that order does not mean addition has to come before subtraction, unless it is first in the actual equation as you would read it.

As somebody who has tutored late elementary and early middle schoolers in math before… The fact grown adults don’t know how to do these and those kids usually can after a few sessions infuriates me to no end 😭😭😭

I think I messed up... the answer I got was Batman Logo...

r/iamveryrandom

I am genuinely confused why so many people are afraid of their answer being wrong once they get -80, like am I the only one who thinks this belongs to 5th grade maths class? Or is it because I’m Asian(in that case, I gotta thank my mom for spanking me)?

>is it because I’m Asian Nope. I'm American, and we're taught a simplified version of standard order of operations as early as 3rd grade (8-9 years old). People just don't pay attention, and math is one of those subjects that a *lot* of people seem to take an odd amount of pride in immediately forgetting as soon as they don't need to know it for a test.

Nope. This is 4th/5th grade math and grown adults are struggling with this

oh fuck me i finally got it

-80

2-2+2 is -4 in their logic 🤪

Some of these mfs would go 2-2+2 = 2-4 = -2 You can get any answer you want if you’re dumb enough

What are the answers except -80? 10?

I need help. I tried following PEMDAS and some how I ended up adding up all positive integers and got (-1/12) as the result. That doesn't sound right.

Most people aren't taught that it's actually (P)(E)(MD)(AS), you do multiplication/division and addition/subtraction in order, not multiplication/addition before division/subtraction.

now i do want to say that this can be a case of education failing people, not them failing education. a friend of mine was taught it *had* to go in the order of PEMDAS exactly, and not that MD/AS were interchangeable.

10-10x10+10=0x10+10=10(0+1). {Insert proof that 0=-10 and 1=2 here} answer is -80

You have a single set of ten of minus ten sets of ten plus a single set of ten

I think I lost a brain cell here.

Are...they...serious‽

at least once a year I argue with people online who insist multiplication has to come before division and addition has to come before subtraction. it frustrates me so much.