The Following MINITAB Output Presents a 95% Confidence Interval Find the Sample Size Needed So That The

question 29

Multiple Choice

The following MINITAB output presents a 95% confidence interval.
$\begin{array}{ccccc}\hline {\text { The assumed sigma }=10.5211} & \\\text { Variable } & \mathrm{N} & \text { Mean } & \text { SE Mean } & 95 \% \mathrm{CI} \\\mathrm{x} & 58 & 39.501 & 1.3815 & (36.793,42.209) \\\hline\end{array}$

Find the sample size needed so that the $95 \%$ confidence interval will have a margin of err 1.2.