Ms. Lisa Monnin is the budget director for Nexus Media Inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample information.
Sales ($)
129
133
147
159
138
143
Audit ($)
125
98
128
135
145
117
141
Click here for the Excel Data File
At the 0.005 significance level, can she conclude that the mean daily expenses are greater for the sales staff than the audit staff?
(a) State the decision rule.
(b) Compute the pooled estimate of the population variance.
(c) Compute the test statistic.