Poll

48÷2(9+3) = ??

28843%43% - 40
256%56% - 51
Total: 91
coke
Aye up duck!
+440|6679|England. Stoke

Winston_Churchill wrote:

Brackets
Exponents
Division
Multiplication
Addition
Subtraction

Therefore its 2.  It is pretty poor notation though.

What if you put in x for (9+3) so that it was 48/2x.  Would you still decide to switch it to 48x/2?
Yeah when you put it that way...
13urnzz
Banned
+5,830|6467

well done, justice.
justice
OctoPoster
+978|6711|OctoLand
Math major here currently taking complex analysis and abstract algebra (not that it has anything to do with this).

You must satisfy the order of operations working from left to right.

48÷2(9+3) = 48÷2*12 = 288.

If you don't understand this, maybe it's time to review some basic arithmetic.
The answer is 288!

Trust me. I'm a high school Calculus teacher and many of my students pass the AP Calculus exam!

P
E
M/D (left to right whichever comes FIRST)
A/S (left to right whichever comes FIRST)

WILL NOT.....I repeat WILL NOT fail you!

As it is written, the answer is 288. The distributive property works because 48/2 = 24! 24(9+3) = 216 + 72 = 288!

By PEMDAS alone it is 48/2(12) = 24(12) = 288! Anyone who says it is 2 is WRONG!

I'm not complaining either. As long as you are around, I'll be employed!
Follow the rules and you get 288. There's no way to split it without ignoring the basics, making you wrong.
This is absolutely hilarious.

My 6th grade son came home with this math problem and I posted it on my facebook page. 5 friends posted it on their pages and now it is around the world. My original post was 9pm central time on 4-6-2011. For what it's worth I said 2 and the 2 engineers I work with agree.
Looking at it like this though:


48 ÷ x(9 + 3) = 288
48 ÷ 9x + 3x = 288
48/12x = 288
4/x = 288
4 = 288x
4/288 = x
1/72 = x


Would suggest that 288 is wrong, and that 2 is correct.


Also, with the order of operations aren't we using the distributive property which states as an example:


Simplify 16 ÷ 2[8 – 3(4 – 2)] + 1.
16 ÷ 2[8 – 3(4 – 2)] + 1
= 16 ÷ 2[8 – 3(2)] + 1
= 16 ÷ 2[8 – 6] + 1
= 16 ÷ 2[2] + 1 (**)
= 16 ÷ 4 + 1
= 4 + 1
= 5


Then, looking at what I have bolded below:



The confusing part in the above calculation is how "16 divided by 2[2] + 1" (in the line marked with the double-star) becomes "16 divided by 4 + 1", instead of "8 times by 2 + 1". That's because, even though multiplication and division are at the same level (so the left-to-right rule should apply), parentheses outrank division, so the first 2 goes with the [2], rather than with the "16 divided by". That is, multiplication that is indicated by placement against parentheses (or brackets, etc) is "stronger" than "regular" multiplication. Typesetting the entire problem in a graphing calculator verifies this hierarchy.

Note that different software will process this differently; even different models of Texas Instruments graphing calculators will process this differently. In cases of ambiguity, be very careful of your parentheses, and make your meaning clear. The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "×" sign) indicates that the juxtaposed values must be multiplied together before processing other operations. But not all software is programmed this way, and sometimes teachers view things differently. If in doubt, ask!

This all seems to point toward 2 being the correct answer.
lol....

Last edited by justice (2011-04-08 14:19:09)

I know fucking karate
Jay
Bork! Bork! Bork!
+2,006|5328|London, England
2

Edit - But my TI-89 says 288 so... 288 is da winner.

Last edited by Jay (2011-04-08 14:23:38)

"Ah, you miserable creatures! You who think that you are so great! You who judge humanity to be so small! You who wish to reform everything! Why don't you reform yourselves? That task would be sufficient enough."
-Frederick Bastiat
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

its 288
Stimey
­
+786|6090|Ontario | Canada
As far as I know its 2.

The 'Brackets' part of BEDMAS also includes factoring a multiple throughout the brackets.
I'm an electrical engineering student trust me here.
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ghettoperson
Member
+1,943|6619

Multiplication is always done before division, so the answer is two.  There's no other way about it, that's why the order of operations exists.
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

48/2x12

work left to right
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

no, multiplication and division are interchangeable.  You do whichever appears first, left to right
13urnzz
Banned
+5,830|6467

Stimey wrote:

I'm an electrical engineering student trust me here.
i work in a building full of engineers, and i wouldn't trust them as far as i could throw them
Beduin
Compensation of Reactive Power in the grid
+510|5720|شمال
lol
الشعب يريد اسقاط النظام
...show me the schematic
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

i will not submit to appeals to authority such as "im an engineering student, trust me"
DrunkFace
Germans did 911
+427|6651|Disaster Free Zone
There is no multiplication operation in the equation.
Jay
Bork! Bork! Bork!
+2,006|5328|London, England

KEN-JENNINGS wrote:

i will not submit to appeals to authority such as "im an engineering student, trust me"
I am an engineer and I said 2


This is why I own a calculator.
"Ah, you miserable creatures! You who think that you are so great! You who judge humanity to be so small! You who wish to reform everything! Why don't you reform yourselves? That task would be sufficient enough."
-Frederick Bastiat
RDMC
Enemy Wheelbarrow Spotted..!!
+736|6535|Area 51
The way I learn it, you'd first do 48/2 = 24 and then 24 * (9+3) = 288

And my Ti-84+ agrees with me.

Last edited by RDMC (2011-04-08 14:26:22)

Jay
Bork! Bork! Bork!
+2,006|5328|London, England

DrunkFace wrote:

There is no multiplication operation in the equation.
Yes there is.

2(9+3) is the same as saying 2 * (9 + 3)
"Ah, you miserable creatures! You who think that you are so great! You who judge humanity to be so small! You who wish to reform everything! Why don't you reform yourselves? That task would be sufficient enough."
-Frederick Bastiat
Stimey
­
+786|6090|Ontario | Canada
BEDMAS is only left sensitive when a sign is given.
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KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

its funny that you guys learn it BEDMAS and we learn it PEMDAS
Jay
Bork! Bork! Bork!
+2,006|5328|London, England

KEN-JENNINGS wrote:

its funny that you guys learn it BEDMAS and we learn it PEMDAS
Well, that does explain the 2 vs 288 conundrum...
"Ah, you miserable creatures! You who think that you are so great! You who judge humanity to be so small! You who wish to reform everything! Why don't you reform yourselves? That task would be sufficient enough."
-Frederick Bastiat
ghettoperson
Member
+1,943|6619

KEN-JENNINGS wrote:

no, multiplication and division are interchangeable.  You do whichever appears first, left to right
Fair enough, guess I'd forgotten all that with years of not using it. In which case what's the debate about? There is a rule for how it works, so follow the rule and you get the right answer. It's not open to debate, it's math.
Spamtheban
Undsiputed BF2s FIFA champion of all time
+132|4812|Stoke

KEN-JENNINGS wrote:

its funny that you guys learn it the right way and we learn it the wrong way
yeah
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

go build another fireplace you plebe
DrunkFace
Germans did 911
+427|6651|Disaster Free Zone

Jay wrote:

DrunkFace wrote:

There is no multiplication operation in the equation.
Yes there is.

2(9+3) is the same as saying 2 * (9 + 3)
No it's an implied multiplication making the second part a single term.

Use any form of substitution and you get 2.

48÷A = ??

A = 2(9+3)


48÷2A =
A9+3)
13urnzz
Banned
+5,830|6467

lol, plebe
KEN-JENNINGS
I am all that is MOD!
+2,973|6602|949

Jay wrote:

KEN-JENNINGS wrote:

its funny that you guys learn it BEDMAS and we learn it PEMDAS
Well, that does explain the 2 vs 288 conundrum...
i was taught that division and multiplication (and addition/subtraction) were interchangeable and you work left to right.  Maybe I was taught wrong though.  There's a reason I didn't pursue a BS...

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