A tough one..

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A tough one..

by moneyman » Fri May 25, 2007 5:19 am
Pls explain..

Each of the students in a certain class received a single grade P,F or I.What % of the students in the class were females?

(1)Of those who received P,40% were females.

(2)Of those who received either an F or I,80% were males.
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by mschling52 » Fri May 25, 2007 5:30 am
Is the answer E?

(1) tells us 40% of those with a P are female, but nothing about those with the other grades. Not Sufficient

(2) tells us 20% of those with I or F are female, but nothing about those with P. Not Sufficient.

(1)&(2) together give us that 40% of those with P and 20% of those with I or F are female. However, we still don't know anything about the % of the class that falls into P, I, or F.

For example, if we assume 100 students and 50 P/50 I or F, then .40(50)+.20(50) = 30 are female. But if the mix was 75 P/25 I or F, then .40(75)+.20(25) = 35 are female.

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by Cybermusings » Fri May 25, 2007 5:40 am
Pls explain..

Each of the students in a certain class received a single grade P,F or I.What % of the students in the class were females?

(1)Of those who received P,40% were females.

(2)Of those who received either an F or I,80% were males.
_________________

Statement I : Clearly insufficient since we do not know anything about female students in other grade groups

Statement II : Insufficient since we do not know anout females in the P grade group

I and II : .4x + .2y = females....Total students = x+y

Hence % of females = .4x + .2x / x+y * 100

However, we can't solve this any further and there are a number of combinations we can use here.. I think it would be E

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Yes

by moneyman » Fri May 25, 2007 8:59 am
Yes..The answer is E..Thanks guys..
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