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GMATPREP - PS problem -1

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by rros0770 » Wed Nov 17, 2010 11:27 am
One Standard Deviation is 6 hours
Mean is 21.

1 Standard Deviation below Mean: 21- 6= 15 hours
2 Standard Deviations below Mean: 21- (2*6)= 21 - (12) = 9 hours

Pat watched television between 1 and 2 SD'd below mean.
SO answer must fall between 9 and 15 hours

Answer: D- 12 hours
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by karanrulz4ever » Wed Nov 17, 2010 11:36 am
1 std deviation below the mean : 21-6 = 15
2 std deviation below the mean : 21-2(6) = 9

answer can be anything between 9 and 15. Out of the choices only 12 applies.
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