GMAT prep - store sold 90 copies

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by Anurag@Gurome » Wed Mar 14, 2012 4:22 am
jkelk wrote:Hi

Please help solve the attached problem

Thanks
J
(1) Last week Store S sold 8 copies on Thursday implies Sun + Mon + Tues + Wednes + 8 + Fri + Sat = 90
If the copies sold by the store are: 1 (Sun) + 0 (Mon) + 2 (Tues) + 3 (Wednes) + 8 (Thurs) + 9 (Friday) + 67 (Sat) = 90, then the store sold less than 11 copies on Friday.
If the copies sold by the store are: 1 (Sun) + 0 (Mon) + 2 (Tues) + 3 (Wednes) + 8 (Thurs) + 14 (Friday) + 62 (Sat) = 90, then the store sold more than 11 copies on Friday.
No definite answer; NOT sufficient.

(2) Last week Store S sold 38 copies on Saturday Sun + Mon + Tues + Wednes + Thurs + Fri + 38 = 90
Now it is given that the store sold the greatest number of copies on Saturday and the second greatest number of copies on Friday. So, if we assume that the store didn't sell more than 11 copies on Friday, then the possibility could be:
6 (Sun) + 7 (Mon) + 8 (Tues) + 9 (Wednes) + 10 (Thurs) + 11 (Friday) + 38 (Sat) = 89 < 90, which clearly implies that the store should have sold more than 11 copies on Friday; SUFFICIENT.

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

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