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Why can't I get this answer??

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by thephoenix » Mon Mar 29, 2010 7:51 pm
farmergrover wrote:If anyone can shed light on the following order of operations program, I would greatly appreciate it! It seems like the most simple problem yet I am stuck..

10-3/4
______

2-1/2

According to the key, the answer is 7 3/4. Can you explain?
10-3/4-x=2-1/22-1/2=3/2

10-3/4=37/4

x=37/4-3/2=(37-6)/4=31/4=7 3/4
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by moliver » Tue Mar 30, 2010 9:20 am
thephoenix wrote:
farmergrover wrote:If anyone can shed light on the following order of operations program, I would greatly appreciate it! It seems like the most simple problem yet I am stuck..

10-3/4
______

2-1/2

According to the key, the answer is 7 3/4. Can you explain?
10-3/4-x=2-1/22-1/2=3/2

10-3/4=37/4

x=37/4-3/2=(37-6)/4=31/4=7 3/4
Sorry theponenix but I don't understand where the x was in the original problem?


thanks
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by farmergrover » Tue Mar 30, 2010 10:14 am
I think it is because if you follow order of operations, you cannot solve the problem as is. If you set it equal to x and then solve for x you can. Am I right?
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by moliver » Tue Mar 30, 2010 10:25 am
ok farmergrover, so the problem has a typo
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by Stuart@KaplanGMAT » Tue Mar 30, 2010 11:13 am
farmergrover wrote:If anyone can shed light on the following order of operations problem, I would greatly appreciate it! It seems like the most simple problem yet I am stuck..

10-3/4
______

2-1/2

According to the key, the answer is 7 3/4. Can you explain?
I'm guessing it's supposed to be a division problem, as follows:

(10 - 3/4) / (2 - 1/2)

We can simplify the numerator to:

10 - 3/4 = 40/4 - 3/4 = 37/4

and the denominator to:

2 - 1/2 = 4/2 - 1/2 = 3/2

giving us:

(37/4) / (3/2)

= (37/4) * (2/3)

= (37*2)/(4*3)

= 74/12

= 37/6

= 6 1/6

However, that doesn't match the answer given, so there's a problem with the original post.
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by gmatmachoman » Tue Mar 30, 2010 12:08 pm
moliver wrote:
thephoenix wrote:
farmergrover wrote:If anyone can shed light on the following order of operations program, I would greatly appreciate it! It seems like the most simple problem yet I am stuck..

10-3/4
______

2-1/2

According to the key, the answer is 7 3/4. Can you explain?
10-3/4-x=2-1/22-1/2=3/2

10-3/4=37/4

x=37/4-3/2=(37-6)/4=31/4=7 3/4
Sorry theponenix but I don't understand where the x was in the original problem?


thanks
Seriously Man, where does that X come from?? Even stuart is also perplexed!
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