A Random Sample of 20 Observations Taken from a Normally $\begin{array}{|l|l|}\hline A&\text {66.546 }\\\hline B&\text {63.454 }\\\hline C&\text {63.812 }\\\hline D&\text {66.188 }\\\hline\end{array}$

Short Answer

A random sample of 20 observations taken from a normally distributed population revealed a sample mean of 65 and a sample variance of 16. The lower limit of a 90% confidence interval for the population mean would equal: $\begin{array}{|l|l|}\hline A&\text {66.546 }\\\hline B&\text {63.454 }\\\hline C&\text {63.812 }\\\hline D&\text {66.188 }\\\hline\end{array}$