Gmat prep

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Gmat prep

by mttorii » Thu Jul 05, 2007 7:34 pm
Hi all. I didn't understand why C is correct...
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by jrbrown2 » Thu Jul 05, 2007 7:47 pm
(1) & (2) are insufficient by themselves.
Together:

Let X = # of Males
Let Y = # of Females

.33X + .2Y = .25 (X+Y)
.33X + .2Y = .25X + .25Y
.08X = .05Y
X=5Y/8

Fraction of males
=X/(X+Y)
=5Y/8 / (5Y/8 + Y)
=5/13