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by beingAndNothing » Mon Dec 24, 2007 5:44 pm
m = 9/25 = 9*32/(25*32) = 288/800

n = 16/32 = 15*25/(25*32) = 375/800

c = 1-m-n = 137/800

w>m>c

Answer (E)
I see that you got the answer as (E). Is the OA not (E)?

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by cks » Mon Dec 24, 2007 6:21 pm
Offical Answer is D

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by preciousrain7 » Thu Dec 27, 2007 5:21 pm
cks wrote:Offical Answer is D
REALLY? I checked with a calculator to make sure and I get A as the answer

9/25=.36 <-- m
15/32=.47 <-- w
1-(.36+.47)= .13 <-- c

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by Auzbee » Tue Jan 01, 2008 1:46 pm
The fastest way to solve this particular problem would be to convert it into percentages. Be careful in such problems if the ratio's are close to each other, then you would have to use the other approaches called out.
m=9/25=36/100 = 36%
w=15/32 (since 33.3 *3 ~100)= 45/96= ~46%
c= 100-46-36=18
hence w>m>c

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by damorris » Sat Jan 05, 2008 5:58 am
I find that the fastest way of approaching this is to consider all fractions in their relationship to one half.

ie,

15/32 is close to one halvf (16/32) and is therefore the greatest

9/25 is further away from one half (12.5/25), and

the remainder is bound to be small and can be double checked with the common denominator (137/800)

The OA is curious (?). I think it should be A. Maybe I could review my idea of what increasing order means. . .

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by roy_priya » Tue Jan 08, 2008 2:58 pm
m = 9/25 is approximately 10/25 = 2/5 = 0.4

w = 15/32 is approximately 16/32 = 1/2 = 0.5

So C = 1 - 0.9 = approx 0.1

So w>m>c.

For me approximation helps to solve such problems faster.

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by Stuart@KaplanGMAT » Tue Jan 08, 2008 9:14 pm
"increasing order" means from smallest to biggest.

Damorris definitely gave the best approach to solving this question. Whenever you see really wacky/annoying numbers on the GMAT, there has to be a better way to solve it than actually doing the calculations. The fractions they give here are easy to estimate relative to 1/2.

c is smallest, m is middle, w is biggest, so in INCREASING order we get:

c, m, w
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