Ratio Propotion DS - GMAT Prep

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Source: — Data Sufficiency |

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by arawamis » Sun Feb 10, 2008 9:30 am
lets see

# of female students in class are F
# of male students in class are M
%80F and %72M applied college or 0.80*F and 0.72*M

(1) says that F+M=840. Info has no use byitself. NOT SUFFICIENT

(2) says that 0.75*(F+M) applied college so 0.75*(F+M) = 0.80*F+0.72*M
==> 0.75F+0.75M=0.80F+0.72M
==> 0.03M = 0.05F
====> M/F = 5/3 . so 5/8 of total students are male. solved SUFFICIENT

Answer is B