Poll: What is the answer to 48/2(9+3)?

[Link_to_Future]

Well this has been an entertaining read. I forget how passionately people can argue about something so banal.

I'll just repeat what has been said before because there really isn't a lot to say. The problem is poorly presented. When I first looked at it I saw 2 because I always make it a point to separate individual fractions by parenthesis as so:

(48/2)*(9+3)

It's clear and unambiguous. There is no argument about how it can be perceived. Without the first set of parenthesis or the multiplication sign, I see it as being in the denominator. Is that wrong? Apparently, and since I'm wrong I'm a bad person and a terrible student who should just flip burgers for the rest of my life. That's how it works, right?

If this were a math problem of any actual bearing to any situation then it would be framed slightly better. Yes, all of you who say its 288 are correct. Technically. But why this sense of superiority that I'm sensing from some of you? What good is it doing honestly?

/preachyrant

 

[Mayki5]

I tried it on my TI-89 and a Casio fx-9750G and the result was 288 regardless of if I entered a multiplication symbol between the 2 and the (. I'm curious as to what calculator was in use given that a mistake of that sort would generally reside at the hardware level and it would necessarily make the same mistake any time an equation of that form were entered.

On my side, Casio FX-83MS, S-V.P.A.M.[/quote]

Found the reason: For my particular model, according to the user manual, operations of equal prescedence are calculated RIGHT to LEFT, not the more common LEFT to RIGHT. Although it still doesn't quite explain why it gets a different answer for one, and not the other. Might be a misinterpretation of the manual on my part. If anybody particularly wants to take a look:
http://support.casio.com/pdf/004/GY300_Dtype_E.pdf

 

[Roggen Bread]

48/(2*(9+3)) or (48/2)*(9+3)?

In Germany a problem formuulated like this was 2.

 

[Darius Brogan]

Both answers are completely correct.

I'm terrible at math... nay... I'm HORRIBLE at math, and in the span of four seconds, I got both 2 and 288 by doing the question both ways (I'm not kidding, my Zero Punctuation episode hadn't even reached the 5 second mark before I paused and came here)

This question is just atrociously vague about which path you take to solve it, therefore, this isn't an issue. Have whoever wrote the equation clarify which path to follow and VOILA!!! You have your answer.

 

[thahat]

2... still remember from grade school, Please Excuse My Dear Aunt Sally; Parentheses, Exponent, Multiply, Divide, Addition, Subtract. So... 9+3=12, 12*2=24, 48/24=2.

but things of the same class go left to right, so not 12*2, but 48/2 = 24
then 24 *12 .

 

[Michael Dagastino]

On the left to right basis it's hard to tell for certain as it could be 48 / (2(12)) or (48/2)*12. It makes more sense to write it out using the ____.

48
----
2*12

or

48
--- *12
2

But generally after the brackets you do go left to right. You don't have to do multiplication before division, just as long as both are done before addition and subtraction.

You said it best. Personally I interpret it as 48 over the quantity of 2 times the sum of 9 plus 3, just because of "/" being used.

 

[timeadept]

This problem illustrates exactly why the order matters. There is only ever one answer to a math problem (well as long as we're dealing with functions like this one anyways). I don't know what to tell you if you don't trust me, but i am 100% sure that you handle division and multiplication whichever comes first from left to right, as with addition and subtraction.

I put this into my TI-83 and it came up with 288 (and it ALWAYS will). If that doesn't convince you that what i said is true, then i cannot convince you.

But addition and subtraction can be done in any order aswell, x-y is the same as -y+x. You can flip them about and juggle them any way you want. The reason we are getting different answers from the expression OP posted is because there's disagreement on what this expression actually is, not because of what order multiplications happen in.

Alright, maybe addition and subtraction can be done in any order, however i'm very tired and can't think of a way to disprove it and so would simply recommend doing it from left to right.

But in any case, if i put this into my calculator it handles it the same way as if it were (48/2)(3+9) There is nothing to imply that the problem is otherwise, yes , i know that it could be argued that there is nothing to imply that 2(3+9) are not all in the denominator however if i were to write that equation it would be 48/(2(3+9)). / is a symbol for division and if you are using it to write fractions then you are using it incorrectly. Yes, you'll get the same effect in most cases but not all.

 

[EHKOS]

Hmmm solve number problems or play video games....bai.

 

[thahat]

Well this has been an entertaining read. I forget how passionately people can argue about something so banal.

I'll just repeat what has been said before because there really isn't a lot to say. The problem is poorly presented. When I first looked at it I saw 2 because I always make it a point to separate individual fractions by parenthesis as so:

(48/2)*(9+3)

It's clear and unambiguous. There is no argument about how it can be perceived. Without the first set of parenthesis or the multiplication sign, I see it as being in the denominator. Is that wrong? Apparently, and since I'm wrong I'm a bad person and a terrible student who should just flip burgers for the rest of my life. That's how it works, right?

If this were a math problem of any actual bearing to any situation then it would be framed slightly better. Yes, all of you who say its 288 are correct. Technically. But why this sense of superiority that I'm sensing from some of you? What good is it doing honestly?

/preachyrant

good explanation, exept for one part. whats so unclear about it?
X and / before - and +, always.basic rule, right?
stuff of the same class go from left to right.
if you jsut stick to that, rigerously. its not unclear at all. exept for the not actually putting down an x or a . ( multlipication = x = . )

 

[captain_dalan]

It's 2. The value of 2(9+3) lies in the denominator; there's no indication that (9+3) is a separate function.

Nothing implies that the entire section "2*(9+3)" is a denominator, but this is the kind of confusion you get when you write equations in non standard model. If the said "2*(9+3)" was to be the denominator it would have to written in the form "(2*(9+3)". Anyone that ever did Basic or Pascal programming would probably notice this

 

[gmaverick019_v1legacy]

What do you guys get for an answer, 2 or 288?

its 288, type it into any "smart" calculator and you will get 288 every single time. just because the stupid phrase has multiplication before division, its actually interchangeable, and you solve left to right to decide the predicament.

 

[Taerdin]

I think what this whole confusion boils down to is that people who do math on paper and never on a computer are not used to using / as a division symbol, and seem to be interpreting it (wrongfully so) as the line you use to divide the numerator and denominator of a fraction.

/ literally is the division symbol on computers. While 1/4 is equivalent to the fraction one over four, 1/4+1 is not equivalent to one over five, it is in fact one quarter plus one, or five over four.

I still can't believe that 41% of people got this wrong though, some of which even admit to having degrees!

 

[thahat]

*looks at results of the poll*
This is basic arithmetic.... Basic BOMDAS....
Faith in Humanity -1

got faith in me? its 288 right XD?

 

[Eclectic Dreck]

Found the reason: For my particular model, according to the user manual, operations of equal prescedence are calculated RIGHT to LEFT, not the more common LEFT to RIGHT. Although it still doesn't quite explain why it gets a different answer for one, and not the other. Might be a misinterpretation of the manual on my part. If anybody particularly wants to take a look:
http://support.casio.com/pdf/004/GY300_Dtype_E.pdf

The only possible reason is that it considers implied multiplication as higher precedent than explicit multiplication. Which after looking at the manual is what it appears to do.

All I'll say is you own a calculator with strange, strange rules. I've never heard of something that calculates from right to left if the precedence is the same. I guess it just teaches you to be more judicious with your use of parenthesis and whatnot.

-EDIT-

For those NOT in the US, do you call these characters "( )" parenthesis or brackets?

For the record, in the US "( )" are parenthesis, "[ ]" are brackets and "{ }" are braces.

 

[Ciran]

What people forget is that PEMDAS is not a hard and fast rule, except for the parentheses and exponent part, after that its left to right.

 

[valkeminator]

Question : 48/2(9+3)?
Answer : 2

= 48 / 2(9+3)
= 48 / ((9x2) + (3x2))
= 48 / (18+6)
= 48 / 24
= 2

Proof that human minds can answer better than computers!
Calculators and Excel/computer will not process this properly unless they are notified of the PEMDAS, try this on excel or calculators if you dont believe it.

Still,it surprises me that most people forgot to prioritize Multiplications over additions/subtractions.

 

[gmaverick019_v1legacy]

Nothing implies that the entire section "2*(9+3)" is a denominator, but this is the kind of confusion you get when you write equations in non standard model. If the said "2*(9+3)" was to be the denominator it would have to written in the form "(2*(9+3)". Anyone that ever did Basic or Pascal programming would probably notice this

Yeah, now that I enter it into a calculator I see where I was wrong.

wait what...hahaha did you copy and paste the guy aboves me post and put it in my quote? i did not say that..although i do agree lol


still, type it in as seen into a calculator and the truth shall set you free!

 

[fat american]

You always multiply what's in the parentheses by the number to the left of the parentheses first. Then take that number and divide by what's left.