Each of the students in a certain class received a single grade of P, F, or I. what percent of the students in the class were females?
1. of those who received a p, 40% were females
2. of those who received either an I or I, 80% were males.
what percent of the students in the class were females?
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I think its E. You can't guage anything by only having percentages without knowing the underlying numbers.
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yeah butosirus0830 wrote:I think its E. You can't guage anything by only having percentages without knowing the underlying numbers.
with p grade number of female=40%
with F or I no. of female=20%
and each student has only one grade
that means there are no overlapping hence
tot % for female=60%
where am i wrng
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1.) 40% p were females - insuffbhumika.k.shah wrote:Each of the students in a certain class received a single grade of P, F, or I. what percent of the students in the class were females?
1. of those who received a p, 40% were females
2. of those who received either an F or I, 80% were males.
2) 20% of I or F were females - insuff
1&2 combined also is insufficient because it doesnt give any picture about how many passed and how many failed
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y we need inf for pass and failajith wrote:1.) 40% p were females - insuffbhumika.k.shah wrote:Each of the students in a certain class received a single grade of P, F, or I. what percent of the students in the class were females?
1. of those who received a p, 40% were females
2. of those who received either an F or I, 80% were males.
2) 20% of I or F were females - insuff
1&2 combined also is insufficient because it doesnt give any picture about how many passed and how many failed
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it is not 40% of the total, it 40% of those passedthephoenix wrote:yeah butosirus0830 wrote:I think its E. You can't guage anything by only having percentages without knowing the underlying numbers.
with p grade number of female=40%
with F or I no. of female=20%
and each student has only one grade
that means there are no overlapping hence
tot % for female=60%
where am i wrng
https://www.beatthegmat.com/gmatprep-1-t ... tml#104869 will help
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I guess you could set up the double column matrix. What you will find though is that with both statements, you still would need totoal percentages for F, I and P in order to answer the question. Right now you just have the number of women that passed equals .4x where x is the total number of those that passed, you don't know what X is though and you have no way of solving for it.thephoenix wrote:yeah butosirus0830 wrote:I think its E. You can't guage anything by only having percentages without knowing the underlying numbers.
with p grade number of female=40%
with F or I no. of female=20%
and each student has only one grade
that means there are no overlapping hence
tot % for female=60%
where am i wrng
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This is a tricky problem. One can mistakenly select C.bhumika.k.shah wrote:Each of the students in a certain class received a single grade of P, F, or I. what percent of the students in the class were females?
1. of those who received a p, 40% were females
2. of those who received either an F or I, 80% were males.
I agree on OA: E.
Combine 1 and 2
Let No of students who received P = x; No of students who received either F or I = y
Total no of student = x+y
Total no of female = 0.4x + 0.2y
%female = (0.4x + 0.2y) / (x+y); This is totally dependent on x and y. So we can't get the fixed value.
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This is a weighted average question.
(1) Females make up 40% of group 1 (P)
(2) Females make up 20% of group 2 (F or I)
Together, Female will make up somewhere between 20% and 40% of the whole population. The exact percentage depends on the ratio of group sizes. If there are twice as many people in group 1, then the percentage will be twice as close to group 1 datapoint (40%) as it is to group 2. On the other hand if there are three times as many people in group 2, then the percentage will be three times as close to group 2 datapoint (20%) as it is to group 1.
E is the answer. A more detailed explanation and step-by-step video solution are available at GMATPrep Question 1151.
-Patrick
(1) Females make up 40% of group 1 (P)
(2) Females make up 20% of group 2 (F or I)
Together, Female will make up somewhere between 20% and 40% of the whole population. The exact percentage depends on the ratio of group sizes. If there are twice as many people in group 1, then the percentage will be twice as close to group 1 datapoint (40%) as it is to group 2. On the other hand if there are three times as many people in group 2, then the percentage will be three times as close to group 2 datapoint (20%) as it is to group 1.
E is the answer. A more detailed explanation and step-by-step video solution are available at GMATPrep Question 1151.
-Patrick
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We are given that each of the students in a certain class received a single grade of P, F, or I. We can let p = the number of students who received P, f = the number of students who received F, and i = the number of students who received I. Thus, the total number of students in the class is p + f + i. We need to determine the percentage of students who were females.bhumika.k.shah wrote:Each of the students in a certain class received a single grade of P, F, or I. what percent of the students in the class were females?
1. of those who received a p, 40% were females
2. of those who received either an I or I, 80% were males.
Statement One Alone:
Of those who received a P, 40 percent were females.
This means 0.4p students are females. However, since we know neither the values of p, f, and i nor the percentage of students who received an F or I, statement one alone is not sufficient to answer the question.
Statement Two Alone:
Of those who received either an F or I, 80 percent were males.
This means 20 percent of the students who received either an F or I were females. In other words, 0.2(f + i) students are females. However, since we know neither the values of p, f, and i nor the percentage of students who received a P, statement two alone is not sufficient to answer the question.
Statements One and Two Together:
From the two statements, we can say that the percentage of students in the class who were females is:
(0.4p + 0.2(f + i))/(p + f + i) x 100
However, since we don't know the values of p, f, and i, we can't determine the numerical value of the expression above. Statements one and two together are still not sufficient.
Answer: E
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