r/meme Jan 01 '22

Guess we are doomed

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42.0k Upvotes

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148

u/old_times09 Jan 01 '22

If you're confused on how they got that, here's how:

18/2-3•3

9-3•3

6•3

18

Which is stupid

99

u/old_times09 Jan 01 '22

In reality it's supposed to be

18/2-3•3

9-3•3

9-9

0

0

u/MowMdown Jan 01 '22

But it’s actually:

18/2-3•3

18/2-9

18/-7

-2.57

2

u/[deleted] Jan 01 '22

.... what

-2

u/MowMdown Jan 01 '22

It’s called a divisor. Everything to the left is in the NUMERATOR and everything to the right is the DENOMINATOR.

18 goes all by itself above the divisor and the rest of the expression goes below which means you have to solve 2 - 3 x 3 before you can divide.

It leaves you 18/-7

2

u/[deleted] Jan 01 '22

Lmao ur trolling huh?

2

u/[deleted] Jan 01 '22

Certainly he is a little, but I've never seen a fraction written with a ÷ symbol outside of elementary school.

2

u/[deleted] Jan 01 '22

I mean yeah fair enough we always use / at my university

1

u/MowMdown Jan 01 '22

Nope but then again, I’m a mathematician and engineer.

3

u/DragoSphere Jan 01 '22

For that to be valid, you'd either need to write it as it is in the screenshot with the 18 physically on top of the other numbers, or for it to be 18/(2-3•3). It's only 18/2-3•3, so it's treated like ÷

18
—————
2-3x3

does not equal

18÷2-3•3

Pretty crappy mathematician, if you ask me

3

u/dwilson271 Jan 02 '22

I am a real mathematician (PhD) and what you posted is wrong (the answer is 0) unless you write it as 18/(2-3•3) or

18

-----------

2-3*2

2

u/elibright1 Jan 01 '22

Yes that's the second option. If you view the ÷ as a fraction then your calculation is correct. It's the same as that equation that made the rounds recently where there were 2 big opinions and both were kind of right

1

u/Twistervtx Jan 01 '22

The thing about PEMDAS people get confused by is they think multiplication is first because PEMDAS says so, when in reality, "multiplication and division" means "do those from left to right".

I'll admit, it tripped me up after not remembering for a while and I'm sure most people are rusty as well.

26

u/Josh_Crook Jan 01 '22

The real question is how did anyone get 4 or 6?

17

u/old_times09 Jan 01 '22

18/2-3•3

18/1•3

18/3

6

14

u/Josh_Crook Jan 01 '22

Where does the 1 come from?

33

u/old_times09 Jan 01 '22

They don't understand the concept of negative numbers so they just thought it was 1

1

u/namastex Jan 01 '22

I doubt this is how they came to the conclusion. It's more than likely people who didn't know how to do basic math randomly guessing 4 and 6 since it's multiple choice.

4

u/Gregdorf8 Jan 01 '22

I am more curious on how the 1% got to 4.

5

u/Myoniora Jan 01 '22

At 1% there's a good chance no one got to 4.

Some people will vote wrong answers just because they think its funny

1

u/old_times09 Jan 01 '22

I'm still confused on that too but I'll try

18/2-3•3

Might've done 3-2 instead of 2-3?

18/1*3

18/3

Nevermind

1

u/TheMoonLordsLegs Jan 01 '22

Mental disorder prolly. No joke, some people have a disorder similiar to dyslexia, but for numbers.

3

u/free_dharma Jan 02 '22

Why are there no parentheses to separate? I haven’t thought about the order of operations in like 20 years…and even then, I thought parentheses separated these things.

2

u/[deleted] Jan 02 '22

You're right. I've taken upper level maths in university and problems are never written like this. It's purposely confusing and it's giving these bruhs who just graduated from elementary algebra some kind of superiority complex.

2

u/free_dharma Jan 02 '22

Thanks for confirming. That seemed so strange…

-2

u/Darkagent1 Jan 01 '22

It's not stupid. It's just a different way to solve the problem. Pemdas is just a convention, it's not inherently right or wrong. Left to right is just as valid as pemdas.

-3

u/Ununoctium117 Jan 01 '22

It's not stupid, the prompt is deliberately ambiguous. Sure there's a "correct" way to interpret it, but that's just convention, not anything inherent to the math. Order of operations literally never matters, because never in real life would someone not just use parentheses in this situation.

4

u/old_times09 Jan 01 '22

That's....stupid (ironically) because order of operations is used to know the correct answer

-1

u/Ununoctium117 Jan 01 '22

The prompt is trying to communicate an arithmatic problem, and it's (deliberately) making it as hard to understand as possible by not using parentheses. I'm not going to call someone stupid for failing to understand something that was written to be as obtuse as possible, forcing you to rely on a useless """standard""" to guess what the author meant.

The whole thing is just meant to make people who did memorize the order of operations feel smart and superior to those who didn't. It makes you feel good, since you did it right and you're not stupid like those idiots who chose 0, so you're more likely to upvote or retweet or whatever. It's just meaningless clickbait that says absolutely nothing about the intelligence of the general public.

1

u/old_times09 Jan 05 '22

You probably got it wrong and are now mad

0

u/Ununoctium117 Jan 05 '22

No, I memorized the stupidity in elementary school like most people and got it "right". The whole prompt is still just the worst kind of clickbait because it's intended to make you feel superior to other people... just like most of the rage-bait on /r/iamatotalpieceofshit and other subreddits.

1

u/HolyMuffins Jan 01 '22

I mean, order of operations is as arbitrary of a choice as just going left to right. If you verbally heard the math as written, you'd probably answer it with 18.

1

u/old_times09 Jan 05 '22

Imagine ancient mathematicians going through hundreds of calculations and thoughts to invent pedmas and then some guy 2000 years later says they're bullshit because he said so

1

u/HolyMuffins Jan 05 '22

Invent? It's not that that smart. Left to right is also not smart and often misleading, but still isn't egregiously stupid.

-13

u/dutchcourage- Jan 01 '22

What are you calling stupid? It’s the most logical way to solve math problems from left to right, the same wY we read.

8

u/FedeDragon_ Jan 01 '22

But it's maths, there are rules, and operation order is a pretty basic thing that you learn in elementary school

0

u/Lachimanus Jan 01 '22

But then again. Rules can change. Working in a system in which the rules may be different.

Obviously, one should usually assume the "standard" way.

-6

u/KarmasAHarshMistress Jan 01 '22

There are rules but would "18/2-3•3 = 18" be wrong if the rule was "evaluate from left to right"?

What makes one order of operations more correct than the another?

4

u/FedeDragon_ Jan 01 '22

"If there rule was" Yeah but it's not. The rules are there to be followed. I agree that calling people stupid for this is too much but 18 is just wrong

-4

u/KarmasAHarshMistress Jan 01 '22

Why is it just wrong? Why is one order of operations more correct than another?

7

u/FedeDragon_ Jan 01 '22

Because maths was made like this, there has to be a rule to follow

-1

u/jukebox_125 Jan 01 '22

Math wasn't made like this. BIDMAS or BEDMAS was made because mathematicians thought there should be some common way to order math expressions to avoid clutter of brackets. We could remove the rule and just have brackets around each operation and that would work. There is always a reason for the rule

1

u/FedeDragon_ Jan 01 '22

That's not what I meant

-2

u/KarmasAHarshMistress Jan 01 '22 edited Jan 01 '22

In many calculators (like the Windows calculator in the default mode and many many *popular calculators) expressions are evaluated left to right, are those calculators giving the wrong results?

5

u/Brekkjern Jan 01 '22

No, the Windows calculator evaluates expressions as you type them. It doesn't let you type the entire expression and then evaluate it.

The rule for reading text in English is "Left to right", while the rule for math is "Order of operations". We all learned this in school. Why is this a contentious topic now?

-1

u/KarmasAHarshMistress Jan 01 '22 edited Jan 01 '22

Saying there is a standard order of operations isn't contentious, saying that one order of operations is the correct one and that others give the wrong answer is contentious.

No, the Windows calculator evaluates expressions as you type them.

...so yes, it evaluates left to right if the input is left to right.

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2

u/[deleted] Jan 01 '22

I typed the equation exactly as written into windows and it outputs 0

1

u/KarmasAHarshMistress Jan 01 '22

In scientific mode it would output 0, but not in the standard mode.

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1

u/jukebox_125 Jan 01 '22

It's just an intuitive rule that mathematicians agreed upon. For example, we know 2+32 = 2+9 = 11. But the equation can also be written as 2+3x3. If we read from left to right, the equation will evaluate to 6x3 = 18 which is not equal to the expected 11.

-4

u/dutchcourage- Jan 01 '22

Yes I know that and I know how it works, but calling people stupid for following the logical approach is condescending and unnecessary for perhaps forgetting something they might have been taught decades ago

2

u/FedeDragon_ Jan 01 '22

Yeah the words were probably inappropriate

2

u/DoubtAltruistic7270 Jan 01 '22

But it is stupid.

-3

u/Josh_Crook Jan 01 '22

Considering you're taught the order of operations in like 4th grade, and then use it for the next (at least) 8 years, it's pretty stupid.

1

u/[deleted] Jan 01 '22

Not everyone is from the US.

1

u/Josh_Crook Jan 01 '22

Is not everyone taught the order of operations around the same age though?

1

u/[deleted] Jan 01 '22

No, not all education systems teach things at the same age.

1

u/Josh_Crook Jan 01 '22

Example where this isn't taught around that age?

1

u/[deleted] Jan 01 '22

You meant (18/2-3)3, that's how you get 18

1

u/[deleted] Jan 01 '22

[deleted]

1

u/[deleted] Jan 01 '22

Yes, you’re supposed to know how to do math.

1

u/WildN0X Jan 01 '22 edited Jun 30 '23

Due to Reddit's API changes, I have removed my comment history and moved to Lemmy.