overlapping set

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overlapping set

by 2010gmat » Sun Nov 08, 2009 6:32 am
are the two questions asking for the same thing or is there a subtle diff??

80% of the lights in a hotel were on at 8.00 pm on some evening. If 40% of lights that were expected to be off, were in fact on, and 10% of lights that were expected to be on, were in fact off; what percent of the lights that are on, are the lights that were not expected to be on? A. 10
B. 12
C. 100/9
D. 8
E. 18

Eighty percent of the lights at Hotel California are switched on at 8 p.m. one evening. However, forty percent of the lights that are supposed to be switched off are actually switched on, and ten percent of the lights that are supposed to be switched on are actually switched off. What percent of the lights that are switched on are supposed to be switched off?

22(2/9)%
16(2/3)%
11(1/9)%
10%
5%

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by palvarez » Sun Nov 08, 2009 7:51 am
No difference, same thing.

of the lights that are [switched] on
lights that were not expected to be on = lights that were supposed to be off

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by 2010gmat » Sun Nov 08, 2009 8:11 am
got it...but took some time to decipher the question... :D

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by vivek.kapoor83 » Mon Nov 09, 2009 4:40 am
pls post the OA for the ques.also with solution

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by 2010gmat » Mon Nov 09, 2009 4:50 am
OA is D for both ques ....

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by vivek.kapoor83 » Mon Nov 09, 2009 11:04 am
can u provide the solution also?