

Solve this equation > 48÷2(9+3) = ? 
View Poll Results: Which is right?  
2  663  55.76%  
288  526  44.24%  
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09042011, 16:35  #176 
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09042011, 16:39  #177 
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I have. What's inside the brackets is 9 + 3 which is 12.
No. I don't know where you're getting that from but it isn't right. There is no such rule. 
09042011, 16:40  #178 
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which would give
48 ÷ 2*9 + 2*3 = neither 288 or 2 a) 2 48  18 + 6 or b) 8.66 (recurring) 48  + 6 18 Of course I would go with b but unless written in long form it still leaves some potential ambiguity. 
09042011, 16:40  #179 
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It's 288.

09042011, 16:47  #180 
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But that's still short form is the sum:
a) 2 48  18 + 6 or b) 8.66 (recurring) 48  + 6 18 Of course I would go with b but unless written in long form it still leaves some potential ambiguity. Although as I wrote it there could be a third version 48  *9 + 2*3 = 24 * 9 + 2*3 = 216 + 6 = 222 2 
09042011, 16:48  #181 
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It's 288.

09042011, 16:51  #182 
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No No!!
I keep looking at this thread and I know every time I come in it'll still be: It's 2 no it's 288 I just can't stand it!! I want to know what the right answer is.. Stamps feet. can we not just ask the person who made all these things up? For some reason this is driving me nuts. 
09042011, 16:51  #183 
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Maybe older posters who were taught in school to do it from left to right are getting 288, whereas those younger like myself, who were taught the bodmas method are getting 2?
How would those who get 288 do this: 48÷2(x+y) ? Or this: 48 divided by 2(9+3) (which is what it says, verbatim, in the OP)? To rationalise to 288, it would read (48÷2)(9+3). 
09042011, 16:52  #184 
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the lack of multiplication sign next to the bracket means that the 2 is affixed to it and therefore should be timsed before the 48 even comes into it because of BODMAS.
BODMAS says calculate what is inside brackets first. Then powers. Then division and multiplication equally working left to right. Finally addition and subtraction equally working left to right. 2(9+3) is calculated in exactly the same way as 2 x (9+3) in every sense. Whether the multiplication sign is there or not has absolutely no effect. It is very poor notation to omit the multiplication sign when using a number before the bracket but it doesn't change how it should be calculated. 
09042011, 17:07  #185 
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To the above poster, I'm going to try something
So we've established that it varies by opinion, but what is 48÷2x(9+3)? Does your answer change? 
09042011, 17:12  #186 
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debate still underway ... seems calculators can come up with different views too!!

09042011, 17:14  #187 
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Did this in school for GCSE's and I'm currently redoing this with Open Uni for maths degree.
Writing it like this:2(9+3) is a short hand version of writing it like this: (2x9)+(2x3). Putting the 2 immediately next to the brackets is algebraic short hand for multiplying the contents of the brackets by the 2. It does not mean whack a multiplication sign in there and then work it out. The ONLY way to get 288 is if there was a multiplication sign after the 2 which there isn't . Those who think this is wrong, the solution is quite simple  put the equation into a scientific calculator verbatim and the answer is 2. End of story. 
09042011, 17:14  #188 
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Ok  can I change camp  I no long say it is 288. In the strictest alegbraic sense.
x=48/2n n=(9+3) Therefore x=48/24 x=2 However, back in the real world, pretty much all software would assume the answer to be 288. Since I write applications to report numbers for a living I have to go with 288 for the real world. Therefore the answer is either, depending if you deal in abstract or if you deal in reality. Can we have this third option added to the poll 
09042011, 17:14  #189 
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48÷2(9+3)  in this equation the answer is 2. You do the brackets first  getting (2x12) which is 24. 48/24 is 2.
(48÷2)(9+3)  in this equation the answer is 288. You do the brackets first and so get 24 x 12=288. 
09042011, 17:14  #190 
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Did this in school for GCSE's and I'm currently redoing this with Open Uni for maths degree.
Writing it like this:2(9+3) is a short hand version of writing it like this: (2x9)+(2x3). Putting the 2 immediately next to the brackets is algebraic short hand for multiplying the contents of the brackets by the 2. It does not mean whack a multiplication sign in there and then work it out. The ONLY way to get 288 is if there was a multiplication sign after the 2 which there isn't . Those who think this is wrong, the solution is quite simple  put the equation into a scientific calculator verbatim and the answer is 2. End of story. Much better than how I tried to explain it. 
09042011, 17:15  #191 
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To the above poster, I'm going to try something
So we've established that it varies by opinion, but what is 48÷2x(9+3)? Does your answer change? and 48÷2x(9+3) = 288 
09042011, 17:16  #192 
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Did this in school for GCSE's and I'm currently redoing this with Open Uni for maths degree.
Writing it like this:2(9+3) is a short hand version of writing it like this: (2x9)+(2x3). Putting the 2 immediately next to the brackets is algebraic short hand for multiplying the contents of the brackets by the 2. It does not mean whack a multiplication sign in there and then work it out. The ONLY way to get 288 is if there was a multiplication sign after the 2 which there isn't . Those who think this is wrong, the solution is quite simple  put the equation into a scientific calculator verbatim and the answer is 2. End of story. 
09042011, 17:17  #193 
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To the above poster, I'm going to try something
So we've established that it varies by opinion, but what is 48÷2x(9+3)? Does your answer change? 48÷2x(9+3) =48÷2x12 =24x12 =288 Whether the multiplication sign is present, or absent and implied by juxtaposition, has absolutely no effect, ever. 
09042011, 17:19  #194 
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if it's (48÷2)(9+3) its 288
if it's 48÷2(9+3) it's 2 THE answer is 42 probably 
09042011, 17:21  #195 
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It does as far as I am concerned 48÷2(9+3) = 2
and 48÷2x(9+3) = 288 My theory, anyway 
09042011, 17:21  #196 
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There is no "opinion" on this amongst mathematicians. There is one unambgious standard and that gives a result of 288.
48÷2x(9+3) =48÷2x12 =24x12 =288 Whether the multiplication sign is present, or absent and implied by juxtaposition, has absolutely no effect, ever. Always do the sum inside the Brackets first. BODMAS. 
09042011, 17:21  #197 
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This makes my head hurt.

09042011, 17:23  #198 
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OMFG!!!
The very fact that there is no sign between the 2 and the brackets means that the 2 belongs to the brackets. People need to realise that BODMAS/BIDMAS is not the only mathematical theory going on here. There is also algebra to think of. EDIT (less confusing explanation) There is no multiplication sign to be put between the 2 and the brackets. 2(9+3) does not mean 2 x (9+3). It means (2x9)+(2x3). Anyone who has successfully studied algebra will know this. 
09042011, 17:25  #199 
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Ok  can I change camp  I no long say it is 288. In the strictest alegbraic sense.
x=48/2n n=(9+3) Therefore x=48/24 x=2 Edited to add  appears to give 
09042011, 17:31  #200 
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OMFG!!!
The whole reason the multiplication sign is there is because it comes immediately before the bracket. The very fact that there is no sign between the 2 and the brackets means that the 2 belongs to the brackets. People need to realise that BODMAS/BIDMAS is not the only mathematical theory going on here. There is also algebra to think of. 2x(9+3) = 18x + 6x = 24x. When you are evaluating an expression, BODMAS is the convention even in algebra. Brackets first. All you have is a multiplication symbol: 2x(9+3) = 2(9+3) = 18+6 = 24. Brackets first. Always. 
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