Difficult PS question from GMAT Prep Question Pack

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by GMATGuruNY » Fri Jun 21, 2013 2:23 am
rishianand7 wrote:Image

Options are:

100
200
300
400
500
Use a Venn diagram to represent all of the YES voters:

Image

The TOTAL who voted YES for M = 500.
The number who voted YES for ONLY M = 200.
Thus, the number who voted YES for BOTH M AND R = 300.

Since the TOTAL number who voted YES for R=400, and 300 of these people voted YES for BOTH M AND R, the number who voted YES for ONLY R = 400-300 = 100.

Adding the values in the Venn diagram, we get:
Total number of YES voters = 200+300+100 = 600.

Since the total number of voters = 800, and 600 of these people noted YES for M, R, or both, the number who did NOT vote YES = 800-600 = 200.

The correct answer is B.
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