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by hja379 » Mon Jan 10, 2011 6:37 pm
What fraction of this year's graduating students at a certain college are males?

1) Of this year's graduating students, 33 percent of the males and 20 percent of the females transferred from another college.
2) Of this year's graduating students, 25 percent transferred from another college.

OA C

I am stumped with this problem. There is no mention of the percentage of males or females from the current college. How could the answer be what it is?
Source: — Data Sufficiency |

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by Night reader » Mon Jan 10, 2011 7:23 pm
hja379 wrote:What fraction of this year's graduating students at a certain college are males?

1) Of this year's graduating students, 33 percent of the males and 20 percent of the females transferred from another college.
2) Of this year's graduating students, 25 percent transferred from another college.

OA C

I am stumped with this problem. There is no mention of the percentage of males or females from the current college. How could the answer be what it is?
given: m=male students, f=female students, s=students, find m/s -?

st(1) m+f=100%; 33m (33% male students) +20f (20% female students) = transferred from another college-? Not Sufficient;
st(2) transferred from another college=25%, current students-? Not Sufficient
Combining st(1&2) [Eq1, m+f=100] and [Eq2, 33m+20f=25(m+f) ] solving the system of equations we get m=500/13 and m/s=500/13 : 100=5/13 Sufficient

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by anshumishra » Mon Jan 10, 2011 7:27 pm
hja379 wrote:What fraction of this year's graduating students at a certain college are males?

1) Of this year's graduating students, 33 percent of the males and 20 percent of the females transferred from another college.
2) Of this year's graduating students, 25 percent transferred from another college.

OA C

I am stumped with this problem. There is no mention of the percentage of males or females from the current college. How could the answer be what it is?
x-> male
y->female

x/(x+y) = ?

Statement 1:
Transferred students from other college : 0.33x + 0.2 y --- Insufficient

Statement 2:
Transferred students from other college : 0.25(x+y) ----- Insufficient

Combining 1 and 2 :
0.33x +0.2 y = 0.25 (x+y) ---- Sufficient, as we can find x and y and hence the ratio, x/(x+y). C
Thanks
Anshu

(Every mistake is a lesson learned )

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by hja379 » Mon Jan 10, 2011 7:34 pm
ThanQ. Made it seem very easy.