A Company That Employs a Large Number of Salespeople Is

A company that employs a large number of salespeople is interested in learning which of the salespeople sell the most: those strictly on commission, those with a fixed salary, or those with a reduced fixed salary plus a commission. The previous month's records for a sample of salespeople are inspected and the amount of sales (in dollars) is recorded for each, as shown in the table.
$\begin{array}{ccc}\text { Commissioned } & \text { Fixed Salary } & \text { Commission Plus Salary } \\\$ 507 & \$ 425 & \$ 492 \\\$ 450 & \$ 443 & \$ 492 \\\$ 532 & \$ 437 & \$ 470 \\\$ 483 & \$ 432 & \$ 439 \\\$ 466 & \$ 444 & \\\$ 410 & &\end{array}$

$\begin{array}{lrccc}\hline \text { ANALYSIS OF VARIANCE } & \text { DF } & \text { SS } & \text { MS } & \text { F } \\\text { SOURCE } & 2 & 4195 & 2097.7 & 3.17 \\\text { FACTOR } & 12 & 7945 & 662.1 & \\\text { ERROR TOTAL } & 14 & 12140 & & \\\hline\end{array}$

Test to determine if a difference exists in the mean sale amounts among the three compensation systems. Test using $\alpha = .025$ .