Recent GMAT Questions from the GMATprep CD.

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by gmatblood » Tue Nov 01, 2011 10:13 am
IMO: 1/4

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by GmatMathPro » Tue Nov 01, 2011 10:15 am
M= her monthly income
12M=her yearly income
x=fraction that she saves each month
1-x=fraction that she does not save each month

So, total amount that she saves is x*12M. This is equal to three times the amount that she DOESN'T save each month, which can be written as 3*(1-x)*M.

Setting them equal:

x*12M=3*(1-x)M

divide out the M from both sides

12x=3-3x

15x=3

[spoiler]x=1/5[/spoiler]
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by rijul007 » Tue Nov 01, 2011 10:19 am
Let her pay be $100

She saves $x each month

12x = 3*(100-x)

12x+3x = 300
x = $20

20/100 = 1/5