Data Sufficiency

Is the number of members of Club X greater than the number of members of Club Y ?
(1) Of the members of Club X , 20 percent are also members of Club Y .
(2) Of the members of Club Y , 30 percent are also members of Club X .

We are asked about the number of members.
We are given the percents of members from x in y and from y in x.
So both are insufficient.

Hence ans IMO is E.

I think the answer is C)

EQUATE 20%OF X TO 30%Y (same people) we can get x/y ratio and hence find who has more members

Whats the OA?

cramya wrote:I think the answer is C)

EQUATE 20%OF X TO 30%Y (same people) we can get x/y ratio and hence find who has more members

Whats the OA?

Correct!

We don't need to solve for the actual number of members, we just want to know which club has more. So, if we can solve for the ratio of x:y, we know the answer.

Since we can combine the statements to form a ratio, (C) is the correct answer to the question.

Hi Stuart and Cramya,
I still could not understand how C is the answer. Can one of u pls explain in detail.
thanks in advance.

Stmt I and II

.20x= .30y (these are the same people)

20x = 30y
x/y=3/2

So club x has more members. we dont ahve to find the number of members here but just who has more hence SUFF

vittalgmat wrote:Hi Stuart and Cramya,
I still could not understand how C is the answer. Can one of u pls explain in detail.
thanks in advance.

Each statement by itself tells us what the overlap between the two groups is. However, individually, they don't give us the whole picture.

Together, we do have the whole picture. From (1), we know that 20% of the members of X are also in Y. From (2), we know that 30% of the members of Y are also in X. Combined, we know that:

20%(X) = 30%(Y)
X/Y = 30%/20%
X/Y = 3/2

Since the ratio of X:Y is greater than 1, there must be more members in X.

Here's another way to think about it:

Let's call the number of people in both groups Z.

Z makes up a smaller piece of the X pie than the Y pie. Therefore, the X pie must be bigger than the Y pie.

I misread the statements(switched my y and x) in my last post and thanks Stuart for correcting that!

I have corrected it.


Regards,
Cramya

Thanks Stuart and Cramya. Now I am clear.

rgds
-V

thanks stuart and cramya. I too made the same mistake as vittal.
will keep this thing in mind.