For each exercise, perform these steps. Assume that all variables are normally or approximately normally distributed.

a. State the hypotheses and identify the claim.
b. Find the critical value(s).
c. Compute the test value.
d. Make the decision.
e. Summarize the results.
Use the traditional method of hypothesis testing unless otherwise specified.

Two groups of randomly
selected drivers are surveyed to see how many miles
per week they drive for pleasure trips. The data
are shown. At α = 0.01, can it be concluded that
single drivers do more driving for pleasure trips on
average than married drivers? Assume σ₁ = 16.7 and
σ₂ = 16.1.

Single drivers 106 110 115 121 132 119 97 118 122 135 110 117 116 138 142 115 114 103 98 99 108 117 152 147 117 154 86 115 116 104 107 133 138 142 140 Married drivers 97 104 138 102 115 133 120 119 136 96 139 108 117 145 114 140 136 113 113 150 101 114 116 113 135 115 109 147 106 88 113 119 99 108 105