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.
A tough one..
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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.
(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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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
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