What fraction are males? I don't get it.
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- Patrick_GMATFix
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It's a weighted avg question. The overall average's proximity to the male and female data points depends on the ratio of male to female group size. If we know how close the weighted avg is to male and female average, we can tell the % breakdown of males and females. The answer is C
QID 1081
-Patrick
QID 1081
-Patrick
Last edited by Patrick_GMATFix on Fri May 21, 2010 4:12 am, edited 1 time in total.
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Let number of male student=100x
Let number of female student=100y
and we are looking for 100x*100/(100x+100y) or 100x/x+y
From 1
33x+20y has been transferred...not sufficient
From 2
25x+25y has been transferred...not sufficient
combining
33x+20y=25x+25y
or 8x=5y or y=8x/5
so x/x+y =x/(x+8/5x) or 5/13..so its 500/13 or 38% approx..sufficient
Ans option C
Let number of female student=100y
and we are looking for 100x*100/(100x+100y) or 100x/x+y
From 1
33x+20y has been transferred...not sufficient
From 2
25x+25y has been transferred...not sufficient
combining
33x+20y=25x+25y
or 8x=5y or y=8x/5
so x/x+y =x/(x+8/5x) or 5/13..so its 500/13 or 38% approx..sufficient
Ans option C
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Thanks guys. Patrick the gmatfix solution was well written. is that solutions engine just for GMATPrep questions? I really like that I can filter questions by topic.