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On April 08 2011 16:41 emesen wrote:Show nested quote +On April 08 2011 16:35 chonkyfire wrote:On April 08 2011 16:33 ISighZ wrote:On April 08 2011 16:27 chonkyfire wrote:On April 08 2011 16:24 Daozzt wrote:On April 08 2011 16:20 chonkyfire wrote:On April 08 2011 16:16 Daozzt wrote:Thanks for linking me the website ^_^ But there's still this: 48 ÷ 2 * (9+3) I forgive you if people read right to left where you're from, but it's 288. it has nothing to do with reading right to left, you have to make 2(9+3) = 24 I'm going to stop responding now since it's hopeless. You've pretty much fried my brain. Not really. I thought it was 288 too 6 pages ago. I'm 100% sure it's 2 no matter what now. May I ask what make you so sure that it's 2? I want to know your explanation 2(9+3) is always 24 there's a difference between 24(9+3) and 48/24 If i read the original problem aloud I get this... 48 divided by 2 times 12... which is 288 i dont read it as 48 divided by 24 because that ignores the order of operations...
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics.
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The poll is quite misleading. But I think most people here don't even begin to understand where the root of the problem lies indeed.
This is just poorly written math expression, with the single purpose of trolling people, based on abusing math semantics.
Should we switch the semantics and use another math notation like LaTex such problem wouldn't exist.
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On April 08 2011 16:44 Hierarch wrote:
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics.
no because you are ignoring the order of operations which says you do what is inside the parenthesis first... which is basic arithmetic and that gives you 12... which makes the problem again a simple 48 divided by 2 times 12 which is 288
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On April 08 2011 16:41 Sarmis wrote:Show nested quote +On April 08 2011 16:21 mcc wrote:On April 08 2011 16:15 Turo wrote:
I guess the point is, there's nothing to solve...
No variable, this basically is just a constant.
Everyone knows constants are boring. Reminds me of a joke from studies. When they asked a CS guy in the first year of uni how much is 2+2, he answered immediately. Student in the second year typed it into a calculator and answered. Student in the third year wrote a program in C to get the answer. Student in the 4th year wrote whole OS designed to solve problems like that and at the end asked : What was the question ? And the student just before final exams angrily shouted : how should I remember all those stupid constants. I'd love to see you prove that the answer to 2+2 is 4. IIRC, it took Russell 300+ pages to prove that 1+1 was 2.
It was a joke  .
Also wasn't Russel trying to prove that from very base axioms ? There is no urgent need to do that, you can just pick axioms appropriately and it should be easier to prove.
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I gotta say, although the poll is a clear troll (well, probably not the OP itself but the "problem" presented) it shows, why it's so damn important that the "language" of maths has to be 100% precise under each and every circumstance imaginable.
I'm a master in law and bachelor in economics, and while in law it's all about interpreting words and phrases, the implications are still (!) nowhere near as dramatic as in maths. If the math expression isn't precise, everything goes down the drain. Good example to show to schoolchildren as to why it's so important to always, always write the correct expression in math.
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The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire term and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it.
So this can be rewritten as:
48 / (2*9 + 2*3)
Which leaves us with
48 / 24 = 2
Answer = 2.
Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 *(9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs..
Source: http://answers.yahoo.com/question/index?qid=20110407104558AAnHvCy
I cant explain it more clearly
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On April 08 2011 08:00 rackdude wrote:
Here's a super easy math problem:
If you get it wrong your IQ is under 3 but greater than 4. And by that I mean, if you think one is wrong because of "technicalities" you learned in an arithmetic class in 7th grade, you lose. It's notation, what is right is the idea, but how we write the idea is just convention...
Poll: Cos((pi)/2) = ?0 (19) 73% (ipsoC)/2 (7) 27% 26 total votes Your vote: Cos((pi)/2) = ? (Vote): 0
(Vote): (ipsoC)/2
Tell me we're not arguing something silly.
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On April 08 2011 15:27 Turo wrote:Show nested quote +On April 08 2011 15:19 chonkyfire wrote:On April 08 2011 15:17 Turo wrote:
Let (9 + 3) = x
so 48/2(9 + 3) => 48/2x
By the second poll, most people believe this to be 48/(2x) = 2.
So why on earth is 288 leading? so its' not 48/2(x)= 288? I'm taking math in Uni right now, and really this is a worthless question. EDIT: not your question xD, the OP's question. 1 - Notation isn't about who can follow the rules the best, it's about clearly conveying the information. If the information isn't clearly conveyed, then it's the failure of whoever wrote it, not who is reading it. 2 - No one would ever write something down like this. There's a reason math is all done by hand, everything is much clearer. (fractions etc.) 3 - This SHOULD have the appropriate brackets. Once again, it's not the failure of the reader, it's the failure of the WRITER, who did not make his/her notation clear. pretty much this + latex
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now i feel dumb
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United States465 Posts
On April 08 2011 16:50 Skrelt wrote:Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 *(9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs.. Source: http://answers.yahoo.com/question/index?qid=20110407104558AAnHvCyI cant explain it more clearly
Wrong, there is no difference between 2(12) and 2*(12)
*Edit for clarity*
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On April 08 2011 16:48 emesen wrote:Show nested quote +On April 08 2011 16:44 Hierarch wrote:
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics. no because you are ignoring the order of operations which says you do what is inside the parenthesis first... which is basic arithmetic and that gives you 12... which makes the problem again a simple 48 divided by 2 times 12 which is 288
No I am not, it's been explained by countless people how both answers are correct, I haven't taken a math course in about 5 years and I still understand how both answers are correct, as stated by many people it's a poorly written equation and due to semantics the answer can be 288 or 2.
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On April 08 2011 16:56 Hierarch wrote:Show nested quote +On April 08 2011 16:48 emesen wrote:On April 08 2011 16:44 Hierarch wrote:
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics. no because you are ignoring the order of operations which says you do what is inside the parenthesis first... which is basic arithmetic and that gives you 12... which makes the problem again a simple 48 divided by 2 times 12 which is 288 No I am not, it's been explained by countless people how both answers are correct, I haven't taken a math course in about 5 years and I still understand how both answers are correct, as stated by many people it's a poorly written equation and due to semantics the answer can be 288 or 2.
no.. the answer of two is only correct if the problem was written as 48/(2(9+3))
that second set of parenthesis makes the difference
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On April 08 2011 16:50 Skrelt wrote:The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire term and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it. So this can be rewritten as: 48 / (2*9 + 2*3) Which leaves us with 48 / 24 = 2 Answer = 2. Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 *(9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs.. Source: http://answers.yahoo.com/question/index?qid=20110407104558AAnHvCyI cant explain it more clearly
Please read the thread.
What you wrote is false. It does not follow from distributive property that 2(9+3). If 2(9+3) is entire term then you can use distributive property to write 2(9+3) = 2*9 + 2*3.
The problem lies in notation used, not in math proper. Both answers are ok, the OP question is bad. 288 is slightly more proper in the sense that notation supporting it is more mainstream.
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people get this wrong because of this --> ÷
I haven't seen that since it got phased out by / back in the 3rd grade.
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On April 08 2011 17:00 mcc wrote:Show nested quote +On April 08 2011 16:50 Skrelt wrote:The distributive property of multiplication CLEARLY states that the 2(9+3) is an entire term and CANNOT be broken up. 2(9+3) follows the distributive property which can be rewritten as (2*9+2*3). Let me repeat the 2 outside of the parenthesis follows the distributive property of multiplication and must be factored and simplified before performing any other operations on it. So this can be rewritten as: 48 / (2*9 + 2*3) Which leaves us with 48 / 24 = 2 Answer = 2. Lastly for those using Google or any other online calculator. These do not understand many theorems or properties so you must explicitly explain what you mean. There is a difference between 48 / 2 *(9+3) and 48 / 2(9+3). The first notation reads 48 / 2 * 1(9+3) while the second reads 48 / (2*9+2*3). Be very careful with your signs.. Source: http://answers.yahoo.com/question/index?qid=20110407104558AAnHvCyI cant explain it more clearly Please read the thread. What you wrote is false. It does not follow from distributive property that 2(9+3). If 2(9+3) is entire term then you can use distributive property to write 2(9+3) = 2*9 + 2*3. The problem lies in notation used, not in math proper. Both answers are ok, the OP question is bad. 288 is slightly more proper in the sense that notation supporting it is more mainstream.
haha yesh i just red it xD. I am sorry for the miscomunication in my post :p
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On April 08 2011 16:57 emesen wrote:Show nested quote +On April 08 2011 16:56 Hierarch wrote:On April 08 2011 16:48 emesen wrote:On April 08 2011 16:44 Hierarch wrote:
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics. no because you are ignoring the order of operations which says you do what is inside the parenthesis first... which is basic arithmetic and that gives you 12... which makes the problem again a simple 48 divided by 2 times 12 which is 288 No I am not, it's been explained by countless people how both answers are correct, I haven't taken a math course in about 5 years and I still understand how both answers are correct, as stated by many people it's a poorly written equation and due to semantics the answer can be 288 or 2. no.. the answer of two is only correct if the problem was written as 48/(2(9+3)) that second set of parenthesis makes the difference
then it should be (48/2)*(9+3) to get 288
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On April 08 2011 16:44 shadowy wrote:
The poll is quite misleading. But I think most people here don't even begin to understand where the root of the problem lies indeed.
This is just poorly written math expression, with the single purpose of trolling people, based on abusing math semantics.
Should we switch the semantics and use another math notation like LaTex such problem wouldn't exist.
Yeah. This is not a "math" problem. This is a problem about ambiguous statements in general. Writing it on a piece of paper properly or using e.g. LateX would eliminate the ambiguity. Can't believe there are so many pages...
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United States465 Posts
The main problem here lies in the way people are treating the distributive property...
They think there is a difference between 3*2(4+1) and 6*(4+1)
288 is the correct answer because what is being distributed is 48/2.
A good definiton is this
The distributive property of multiplication over addition is simply this: it makes no difference whether you add two or more terms together first, and then multiply the results by a factor, or whether you multiply each term alone by the factor first, and then add up the results.
It does not say that to evaluate 2(4+1) you first do (2*4 + 2*1) it says that when you multiple something in parenthesis by a term (In this case, by order of operations the term that is multiplied is 48/2 because before the multiplication into the parenthesis the division must first be completed) and when you multiply the term into the parenthesis you can evaluate it as either
24(9+3) OR (24*9+24*3)
However you cannot first multiply the 2 in before dividing by order of operations
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results of 1st and 3rd poll dont align, right?
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On April 08 2011 16:57 emesen wrote:Show nested quote +On April 08 2011 16:56 Hierarch wrote:On April 08 2011 16:48 emesen wrote:On April 08 2011 16:44 Hierarch wrote:
The 2(9+3) can read as distribute 2 throughout the parenthesis which leads to 24, 18+6 as has been stated multiple times and by two calculators, both answers could be correct based on perspective and semantics. no because you are ignoring the order of operations which says you do what is inside the parenthesis first... which is basic arithmetic and that gives you 12... which makes the problem again a simple 48 divided by 2 times 12 which is 288 No I am not, it's been explained by countless people how both answers are correct, I haven't taken a math course in about 5 years and I still understand how both answers are correct, as stated by many people it's a poorly written equation and due to semantics the answer can be 288 or 2. no.. the answer of two is only correct if the problem was written as 48/(2(9+3)) that second set of parenthesis makes the difference
Again please read the thread, especially about what notation is, and then make an argument.
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EPT
