Thread: Ummm

48÷2(9+3) = ? | Know Your Meme

this is where i got it from

and here is the order of operations

http://en.wikipedia.org/wiki/Order_of_operations

terms inside parentheses or brackets
exponents and roots
multiplication and division As they appear left to right
addition and subtraction As they appear left to right

As they appear left to right, so its 288, there can be no other answer

Yes, but with an implied operator, I'm not sure of the order. say you had 2 / 5i. 5i is 5 * i, but it's implied that they are to be grouped together.

288 is the answer depending on how you do it. It's just confusing because the troll who came up with this purposefully wrote it in a silly notation to be misleading. People tend to distribute before they go from left to right.

48 ...12
--- x --- =
2...... 1


You can't multiply this without dividing 48 by 2 first.

The question's simply designed to be ambiguous (and thus the question is incorrect math, essentially)... it really doesn't merit any discussion. I would be inclined to read it 48÷(2(9+3)) because that's the nuance of the brackets, but (48÷2)(9+3) is just as 'valid'.

The only incorrect answer is to claim that there is a single well-defined answer. There isn't. There isn't any left-to-right 'rule' or anything for deciding this.

Awesome, thanks Xei

> That feel when for all your knowledge of Sturm-Liouville theory and the isomorphism theorems, people just see you as an authoritative source for questions about basic arithmetic.

What Xei said, it's ambiguous.

But I got 2, that's what I did when I first looked at it.

I got 2 first. Also, I have a question. I never heard of BEDMAS, but learned PEMDAS. Is PEMDAS one of those things America does differently for no appearent reason? Sort of like how we don't use the metric system (even though BEDMAS and PEMDAS are the same thing written different.)

It's only of limited accuracy anyway... it suggests that 1 - 2 + 3 is 1 - (2 + 3), but really you take it term by term (i.e. 1, -2, + 3, in any order, which gives you a different answer to 'BEDMAS'). Brackets then powers then multiplication then addition is the only important and correct thing.

Originally Posted by Xei

> That feel when for all your knowledge of Sturm-Liouville theory and the isomorphism theorems, people just see you as an authoritative source for questions about basic arithmetic.

Dick.

According to my graphing calculator the answer is 288, so...

I'm pretty sure that calculators (and computers) will just do it from left to right when the precedence is the same. If it sees 48/2 and then something after the 2, it will assume what's after isn't in the denominator anymore, unless there are brackets like 48/(2*12).

EDIT: I didn't see the second page of this before typing all of that above until now.

So yay, Xei has come to the rescue, and said exactly what I did at first. But no one listened to me.

I did find a website teaching grade school math in which a 2 / 3 * 5 type of question was brought up, and in the example they said to do division first. So maybe it is still a technical rule for grade-school math, when it's written otherwise ambiguously.

Nobody uses the division symbol after 3rd grade mathematics. Which is why people become confused as to what the answer is. The question is written totally wrong for the purpose of being ambiguous as what Xei has said.

Also different calculators will present the answer differently.


So the question was basically created to troll people.

Originally Posted by siuol

I got 2 first. Also, I have a question. I never heard of BEDMAS, but learned PEMDAS. Is PEMDAS one of those things America does differently for no appearent reason? Sort of like how we don't use the metric system (even though BEDMAS and PEMDAS are the same thing written different.)

I use PEMDAS as well (American) and it is just the same thing. I'm not sure if its national trends or if its just coincidental depending on who teaches it and where they learned their information. This was the first time I've seen BEDMAS though. Or maybe it is one of those things like metric because WERE AMERICA! To use metric would surrender our sovereignty!
(Sarcasm for clarification to those of you who can't tell in text.)

Originally Posted by Dianeva

So yay, Xei has come to the rescue, and said exactly what I did at first. But no one listened to me.

dw, I listened to you too. And I was just about to say that you said it already until I saw this post lol
I also said a similar thing on the other page too, that it's nonsensical if it's not applied to something. As it could really be done any way.
Although I'm not sure how good my last post's argument was at showing it can only be done one way.