forgmat wrote:
70, 75, 80, 85, 90, 105, 105, 130, 130, 130
The list shown consists of the times, in seconds, that it took each of 10 schoolchildren to run a distance of 400 on of meters. If the standard deviation of the 10 running times is 22.4 seconds, rounded to the nearest tenth of a second, how many of the 10 running times are more than 1 standard deviation below the mean of the 10 running times?
A. one
B. two
C. three
D. four
E. five
Bunuel It looks like "on of" should be removed in the first sentence. Thanks!
Statistics : Posted by GMATCoachBen • on 21 Aug 2007, 17:27 • Replies 21 • Views 29460
