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## View Poll Results: ？

1. 40 26.85%
9. 99 66.44%
Hard to say. 8 5.37%
Voters: 149. You may not vote on this poll

 Oct 10th, 2012, 05:14 PM #76 pov Senior Member     Join Date: Feb 2008 Posts: 10,441 Re: 6÷2（2+1）=？ Order as I know it is: parentheses 6/2(3) multiplication 6/6 division 1 I'm surprised so many did division before multiplication giving 9 __________________ "The human mind is not capable of grasping the Universe. We are like a little child entering a huge library. The walls are covered to the ceilings with books in many different tongues. The child knows that someone must have written these books. It does not know who or how. It does not understand the languages in which they are written. But the child notes a definite plan in the arrangement of the books - a mysterious order which it does not comprehend, but only dimly suspects." - Albert Einstein
 Oct 10th, 2012, 05:26 PM #77 Kingpova The King is judging you.     Join Date: Apr 2008 Location: Under the sea. Posts: 17,508 Re: 6÷2（2+1）=？ 1. I said 9 before but I consulted my old textbook on parenthesis and I change my answer. BOMDAS Brackets off Multiply Divide Add Subtract. __________________ Part-Time Pianist Corporate Drone Pirru ShuShoe JellyD Shitra JJuggs VIP Cheaterlenko Pavs Help Polo Svito Rusless ITFanovic Unattractive-Insideraki PopCon 2013. Vote Now!
Oct 10th, 2012, 06:47 PM   #78
silverwhite
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Re: 6÷2（2+1）=？

I thought it was 1 too but I was complacent and didn't think carefully

6 ÷ 2 (2+1) = 6 ÷ 2 x (2+1) = 9

The first and second expressions are equivalent

Quote:
 Originally Posted by Morning Morgan Seriously the aim of these kind of questions is just to trick people, because with sufficient use of brackets all ambiguity can be avoided.
Agreed. Personally, I'm used to seeing and I'm used to using brackets for multiplication when that particular term is involved in addition/subtraction (eg. 6 + 2 (2+1) ). That's why I instinctively did "2 (2+1) = 6" in my head first. It's a reflex

If I had to write this particular expression, I would always use the multiplication sign to avoid any ambiguity (i.e. 6 ÷ 2 x (2+1) )
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Oct 10th, 2012, 07:04 PM   #79
PhilePhile
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by silverwhite I thought it was 1 too but I was complacent and didn't think carefully 6 ÷ 2 (2+1) = 6 ÷ 2 x (2+1) = 9 The first and second expressions are equivalent Agreed. Personally, I'm used to seeing and I'm used to using brackets for multiplication when that particular term is involved in addition/subtraction (eg. 6 + 2 (2+1) ). That's why I instinctively did "2 (2+1) = 6" in my head first. It's a reflex If I had to write this particular expression, I would always use the multiplication sign to avoid any ambiguity (i.e. 6 ÷ 2 x (2+1) )
No. To avoid ambiguity, (6÷2)x(2+1) if the desired answer is 9.

Oct 10th, 2012, 07:08 PM   #80
silverwhite
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by PhilePhile No. To avoid ambiguity, (6÷2)x(2+1) if the desired answer is 9.
It depends on how you see it. I personally prefer 6 ÷ 2 x (2+1)
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Oct 10th, 2012, 07:12 PM   #81
Kon.
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by pov Order as I know it is: parentheses 6/2(3) multiplication 6/6 division 1 I'm surprised so many did division before multiplication giving 9
This isn't the correct order of operations though.
It is:
Parentheses
Exponents
Multiplication-Division
Multiplication doesn't go before division. Neither has precedence over the other. Same thing with addition and subtraction. They happen at the same time.
Then you just operate from left to right.

In this case we have 6 ÷ 2 (3) so the reason it's 9 is than you first have to do the division because it's on the left, getting 3 (3) =9.

Oct 10th, 2012, 07:14 PM   #82
PhilePhile
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by silverwhite It depends on how you see it. I personally prefer 6 ÷ 2 x (2+1)
There is no "personally prefer" in arithmetics, either you follow the rules or be as clear as possible.

Oct 10th, 2012, 07:15 PM   #83
silverwhite
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by PhilePhile There is no "personally prefer" in arithmetics, either you follow the rules or be as clear as possible.
Explain how (6÷2)x(2+1) is objectively clearer
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 Oct 10th, 2012, 07:23 PM #84 Mary Cherry. .     Join Date: Jan 2010 Posts: 10,939 Re: 6÷2（2+1）=？ I still don't get how you can put 2(2+1) as 2 x 3. I know the number outside the bracket means you should times it by what's inside the bracket and since brackets come first, shouldn't you do 2(3) before the division? I don't remember them teaching us that you get marks for re-writing the question.
Oct 10th, 2012, 07:24 PM   #85
silverwhite
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by Mary Cherry. I still don't get how you can put 2(2+1) as 2 x 3. I know the number outside the bracket means you should times it by what's inside the bracket and since brackets come first, shouldn't you do 2(3) before the division? I don't remember them teaching us that you get marks for re-writing the question.
What's inside the brackets comes first
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 Oct 10th, 2012, 07:24 PM #86 LoveFifteen Gone with the Wind fabulous!     Join Date: Jun 2005 Location: Washington, DC Posts: 8,499 Re: 6÷2（2+1）=？ The answer is 1, but if anything, this problem just demonstrates how stupid random math problems are.
Oct 10th, 2012, 07:28 PM   #87
Mary Cherry.
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by silverwhite What's inside the brackets comes first
Well yes, that's how you know to times the 2 by 3. I still don't get how you can rewrite the question and add the x in yourself though. The 2 is grouped with what's in the bracket, not with the 6.

Oct 10th, 2012, 07:28 PM   #88
Mary Cherry.
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by LoveFifteen The answer is 1, but if anything, this problem just demonstrates how stupid random math problems are.
Pretty much.

Oct 10th, 2012, 07:30 PM   #89
young_gunner913
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by Mary Cherry. Pretty much. Let's end the thread here
We can end the thread with that statement and the correct answer: 9.
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Oct 10th, 2012, 07:30 PM   #90
Inger67
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Re: 6÷2（2+1）=？

Quote:
 Originally Posted by Mary Cherry. I still don't get how you can put 2(2+1) as 2 x 3. I know the number outside the bracket means you should times it by what's inside the bracket and since brackets come first, shouldn't you do 2(3) before the division? I don't remember them teaching us that you get marks for re-writing the question.
That is multiplication then, not considered brackets anymore. You just do what is inside the brackets first.

Quote:
 Originally Posted by LoveFifteen The answer is 1, but if anything, this problem just demonstrates how stupid random math problems are.
Can you please explain how you get 1?

As many people have said before (as myself) you do what's INSIDE the parenthesis (brackets) first and then divide and multiply. Since those steps come in the same order of PEMDAS (P, E, M&D, A&S to make it clearer) you do what comes first, i.e. LEFT to RIGHT.

6 divided by 2 and then 3(3) = 9
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