If 2/5 of the students at College C are business majors, what is the number of female students at College C?
1) 2/5 of the male students at College C are business majors.
2) 200 of the female students at College C are business majors.
OA: C
Would anyone please explain?
I answer B because I thought that:
From the info:
2/5 * (total) = business major
total = M + F
2/5 * (M + F) = business major
2/5*M + 2/5*F = business major
1) 2/5*M are business major (I thought we already know that from the information given)
2) 2/5*F = 200 so F = 500
That's why I thought statement 2 alone is sufficient....would anyone please explain at which point I was wrong???
Appreciate all the help!
If 2/5 of the students at College C (GMATPrep)
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you are right!!
just one mistake..
you combined the information you got from the statement 1 with the information from 2.
and thats why the answer should be C.
2/5*M are business major-- thats not from the question stem. thats from statement 1.
just one mistake..
you combined the information you got from the statement 1 with the information from 2.
and thats why the answer should be C.
2/5*M are business major-- thats not from the question stem. thats from statement 1.
The powers of two are bloody impolite!!
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Can you not simplify the problem as Freshy had done?
I understand what he had done by believing he already had data 1, but I want to say that kind of simplification cannot be done and I'm hoping someone can explain it to me.
That was pretty slick how you did that, Freshy. I didn't think about doing that.
I understand what he had done by believing he already had data 1, but I want to say that kind of simplification cannot be done and I'm hoping someone can explain it to me.
That was pretty slick how you did that, Freshy. I didn't think about doing that.
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you can of course do it.georgeung wrote:Can you not simplify the problem as Freshy had done?
I understand what he had done by believing he already had data 1, but I want to say that kind of simplification cannot be done and I'm hoping someone can explain it to me.
That was pretty slick how you did that, Freshy. I didn't think about doing that.
lets say there are 100 students...
40 male and 60 female. if we say 2/5 of the students are business majors.
and if you know that 2/5 of male are business majors. then 2/5 of the remaining group..i.e. females must be business majors.
The powers of two are bloody impolite!!
the mistake freshy makes is that
because (2/5)T = BM
and T = M+F
we can not assume (2/5)M + (2/5)F = BM
It should be (2/5)(M+F) = (x)M + (y)F.
From st 1: (x)M = (2/5)M
which gives us (2/5)(M+F) = (2/5)M + (y)F
but it is insufficient as it does not give a value for F
However, we get to know that (y)F has to be (2/5)F
St2: says (y)F = 200
but we do not know y. (y can 2/5 or 3/5....)
so Insuff
combining the 2,
we get to know that (y)F = (2/5)F = 200.
So F = 500.
Hence C.
Hope this helps.
because (2/5)T = BM
and T = M+F
we can not assume (2/5)M + (2/5)F = BM
It should be (2/5)(M+F) = (x)M + (y)F.
From st 1: (x)M = (2/5)M
which gives us (2/5)(M+F) = (2/5)M + (y)F
but it is insufficient as it does not give a value for F
However, we get to know that (y)F has to be (2/5)F
St2: says (y)F = 200
but we do not know y. (y can 2/5 or 3/5....)
so Insuff
combining the 2,
we get to know that (y)F = (2/5)F = 200.
So F = 500.
Hence C.
Hope this helps.
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That's where I'm not totally clear. I operate based on mathematical principles, so based on a simple principle thatben wade wrote:the mistake freshy makes is that
because (2/5)T = BM
and T = M+F
we can not assume (2/5)M + (2/5)F = BM
It should be (2/5)(M+F) = (x)M + (y)F.
x*(a+b)=x*a+x*b
What is wrong with assuming that
2/5*(M+F) not equal to 2/5*M+ 2/5*F
i know im making some sort of an implicit assumption wrong but can't put a finger to it.