
Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion 
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May 18th, 2012, 05:08 PM  #1 
Newbie Joined: May 2012 Posts: 2 Thanks: 0  I'm sure this has been brought here before
Hi, 6/2(2+1)= X about 10 people in my office say the answer is 9. A friend of mine and I say is 1 Well I did a search over the internet and most of people say is 9 The way they see it is like this: (6/2) x (2+1)= 3x3=9 My friend and I see it like this 6/(2(2+1))=6/(2x3)= 6/6=1 When I do it in excel and calculators the answer is 9 but is obvious the calculator does not know about omitted parenthesis (which we human know). Therefore, it cannot do the calculation correct. Also if I say the equation is 6/a=x and a=2(2+1)=6. Then 6/a=6/6=x=1 
May 18th, 2012, 05:28 PM  #2 
Math Team Joined: Oct 2011 From: Ottawa Ontario, Canada Posts: 14,111 Thanks: 1002  Re: I'm sure this has been brought here before
Answer is 9. 6 / (2(2+1)) = 1. What's in brackets is done FIRST: (2 + 1) = 3 Then the division: 6/2 = 3 Then the multiplication: 3 * 3 = 9. 
May 18th, 2012, 06:04 PM  #3 
Newbie Joined: May 2012 Posts: 2 Thanks: 0  Re: I'm sure this has been brought here before
yes the answer is 9. I did a research and that is the number. thanks, 
May 18th, 2012, 06:23 PM  #4  
Senior Member Joined: Apr 2011 From: USA Posts: 782 Thanks: 1  Re: I'm sure this has been brought here before Quote:
then there's like an "understood" parenthesis in the denominator. But you did not write it like that. You wrote it out on one line, meaning you have to include those parenthesis if that is what you mean, and no one could assume there was supposed to be something there. So no, we don't have the ability to know about "omitted" parenthesis. In fact, this causes problems around here all the time cause we never know what someone "meant" to do.  
June 19th, 2012, 07:20 AM  #5 
Newbie Joined: Apr 2012 Posts: 18 Thanks: 0  Re: I'm sure this has been brought here before
um i think the the order should be 1) brackets (B) 2)of (O) 3)divide (D) 4)multiply (M) 5)add (A) 6)subtract (S) 
June 19th, 2012, 12:12 PM  #6  
Global Moderator Joined: Nov 2009 From: Northwest Arkansas Posts: 2,766 Thanks: 4  Re: I'm sure this has been brought here before Quote:
Quote:
Ah. viewtopic.php?f=13&t=20148&p=79150#p79150  