Question

Suppose that, based on a sample, the 95%% confidence interval for the mean of a population is (21,37). What is the value of s/√n?

A.4
B.3
C.5
D.2

Answer 1

A.4

Explanation:

Based on a sample, the 95%% confidence interval for the mean of a population is (21,37). Therefore, the value of s/√n is 4.

Answer 2

A. 4

Explanation:

s/√n is the sample standard deviation. 95% is approximately between ±2 standard deviations, so the ends of the interval are 4 standard deviations apart.

s/√n = (37 − 21) / 4

s/√n = 4