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Club X and Club Y

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Club X and Club Y

by zagcollins » Mon Jul 21, 2008 8:05 am
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.
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Source: — Data Sufficiency |
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by cubicle_bound_misfit » Mon Jul 21, 2008 9:07 am
IMO it is C.

using set theory we get

X/5 = 3/10 Y

hence X = 15/10 Y

as X,Y >0 and belongs to Integer.

let me know OA please.

regards,
Cubicle Bound Misfit
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by Canman » Mon Jul 21, 2008 9:17 am
Can you walk me through the set theory in a little more detail?

When I run through the problem quickly picking a few numbers and drawing some venn diagrams, I can come up with multiple scenarios where either X is greater, less than or equal to Y that will still satisfy the overlap restrictions of the two statements together.

Thanks!
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by zagcollins » Mon Jul 21, 2008 10:11 am
OA is C...Cubicle bound misfit, can you walk me through the problem in a more simplistic manner? i didnt understand the set theory at all...
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by reachac » Mon Jul 21, 2008 10:43 am
It can be simplified by taking
20% ox X = 30%of Y

Hence X > Y
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by pepeprepa » Mon Jul 21, 2008 1:17 pm
With the two sentences,
There are people who are in X, people who are in Y and people who are in X and Y.
The number of people who are in X and who also are in Y is the same number as the one of Y who are alos in X.
But we see that this proportion of people who are in both is different between X and Y.
It represents much more for Y than for X so Y is smaller than X.

Example:
150 persons in X
90 persons in Y
30 persons represents only 30/150=20% of X but 30 persons represents 30/90=33,3% of Y
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