Question

A police officer is concerned about speeds on a certain section of Interstate 95. The data accompanying this exercise show the speeds of 40 cars on a Saturday afternoon.

Click here for the Excel Data File (HwySpeed
69
70
66
70
69
65
70
70
65
69
70
68
67
70
70
67
69
66
66
66
65
70
69
70
69
66
69
65
68
70
68
69
69
69
67
66
67
68
68
66

Click here for the CSV Data File

(HwySpeed
69
70
66
70
69
65
70
70
65
69
70
68
67
70
70
67
69
66
66
66
65
70
69
70
69
66
69
65
68
70
68
69
69
69
67
66
67
68
68
66

a. The speed limit on this portion of Interstate 95 is 66 mph. Specify the competing hypotheses in order to determine if the average speed is greater than the speed limit. H0: μ = 66; HA: μ ≠ 66 H0: μ ≥ 66; HA: μ < 66 H0: μ ≤ 66; HA: μ > 66

b-1. Calculate the value of the test statistic. (Round your answer to 3 decimal places.)

b-2. Find the p-value. 0.020 p-value < 0.05 p-value 0.10 p-value < 0.01 0.01 p-value < 0.020 0.05 p-value < 0.10

c. At α = 0.10, are the officer’s concerns warranted?

Answer 1