The Two Samples Whose Statistics Are Given in the Table

Multiple Choice

The two samples whose statistics are given in the table thought to come from populations with
Equal variances. What is the pooled estimate of the population standard deviation? $$\begin{array} { | c | c | c | } \hline \boldsymbol { n } & \text { Mean } & \text { SD } \\\hline 50 & 22 & 3 \\\hline 55 & 25 & 4 \\\hline\end{array}$$

A) 3.52
B) 5.00
C) 3.56
D) 1.87
E) 3.50