Question

A sample of 64 was taken from a population, with the mean of the sample being 43 and the standard deviation of the sample being 6. What is the 95% confidence interval for the mean of the population?

A. (42.25, 43.75)
B. (37.3, 48.7)
C. (41.5, 44.5)
D. (37, 49)

Answer 1

C. (41.5, 44.5)

Explanation:

Answer 2

C. (41.5, 44.5)

Explanation:

Point estimate of population variance:

64(6²)/63

256/7

xbar +/- [z × sqrt(var/n)]

43 +/- [1.96 × sqrt(256/7 ÷ 64l]

43 +/- 1.481620735

[41.51837927 , 44.48162073]