A 99% confidence interval for the mean $\mu$ of a normal population when the standard deviation $\sigma$ is known is found to be 98.6 to 118.4. If the confidence level is reduced to .95, the confidence interval for $\mu$
A) becomes wider
B) becomes narrower
C) remains unchanged
D) None of the above answers are correct.

Question

Quizplus · Accepted Answer

When the confidence level is reduced (from 99% to 95%), the z-score associated with the confidence interval decreases, resulting in a narrower confidence interval.

A 99% Confidence Interval for the Mean μ\muμ Of a Normal Population When the Standard Deviation

A 99% Confidence Interval for the Mean $\mu$ Of a Normal Population When the Standard Deviation