The following data represent the running times of random samples of films produced by 2 motion-picture companies:
Company Time (minutes)
A 102 86 98 109 92
B 81 165 97 134 92 87 114
At the 1% level of significance, test the hypothesis that the average running time of films produced by Company A is less than that of Company B. Assume the distributions of running times at both companies are roughly normal.
Note: An unpooled variance t-statistic, if appropriate, would have 7 degrees of freedom.
(a) State the null and alternative hypotheses.
(b) Calculate the value of an appropriate test statistic.
(c) Construct the rejection region.
(d) What do you conclude? (Interpret your result.)