The Following Dotplot Displays the Salaries of the 23 Presidents

Short Answer

The following dotplot displays the salaries of the 23 presidents of California State University campuses for the 2007\_08 academic year:
These salaries, arranged in order, are listed here:
$\begin{array}{llllllll}258,680 & 270,000 & 270,315 & 270,568 & 275,000 & 276,055 & 279,500 & 285,000 \\290,000 & 291,179 & 292,000 & 295,000 & 295,000 & 295,000 & 295,000 & 297,870 \\298,749 & 299,000 & 299,435 & 305,008 & 320,329 & 325,000 & 328,209 & \\\end{array}$
a. Determine the five-number summary of these salaries. Consider the following computer output:
$\begin{array}{llll}Variable & N & Mean & StDev \\salary & 23 & 291,822 & 17,669 \\\end{array}$
b. The salary for Cal Poly's President Baker is $\$ 328,209$ . Calculate the $z$ -score for his salary, and decide whether his salary is more than two standard deviations above the mean.
c. Check whether President Baker's salary is an outlier, according to the 1.5 _ IQR rule.