Given a mean of 12 and a standard deviation of 2, we can conclude that:
A)95 percent of cases are between 10 and 14.
B)68 percent of cases are between 10 and 14.
C)all of our data are between 10 and 14.
D)there is not enough information to make any conclusions.
E)95 percent of cases are between 11 and 13.

Question

Quizplus · Accepted Answer

The correct choice is based on the empirical rule, which states that for a normal distribution, approximately 68% of the data falls within one standard deviation of the mean. Given a mean of 12 and a standard deviation of 2, one standard deviation below the mean is 10 (12-2) and one standard deviation above the mean is 14 (12+2), thus 68% of cases are between 10 and 14.

Given a Mean of 12 and a Standard Deviation of 2