Question

29. When the level of confidence and the sample size remain the same, a confidence interval for a population mean µ will be _____, when the sample standard deviation s is smaller than when s is larger.

A. narrower

B. sometimes wider, sometimes narrower

C. wider

D. the same

Answer 1

Question 29)

When the level of confidence and the sample size remain the same, a confidence interval for a population mean µ will be narrower when the sample standard deviation s is smaller than when s is larger.

Note: confidence interval for population mean when sampl srandard deviation is given as follows,

Therefore, when samle standard deviation is small.then margin of error ( E) is also get small and interval becomes narrower.