If the mean is 10 for a given variable,and the standard deviation is 1,then 99.9 percent of cases are between which two values?
A)8 and 12
B)7 and 13
C)6 and 14
D)5 and 15
E)4 and 16

Question

Quizplus · Accepted Answer

For a normal distribution, approximately 99.7% of cases lie within 3 standard deviations of the mean. Since the standard deviation in this case is 1, we can say that 99.7% of cases lie within the range of 10-3 to 10+3, which is 7 to 13. Therefore, the best choice is B.

If the Mean Is 10 for a Given Variable,and the Standard