Question

6. Suppose a random sample of 10 types of compact cars reveals the following one-day rental prices (in dollars) for Hertz and Thrifty, respectively:

Hertz: 37.16, 14.36, 17.59, 19.73, 30.77, 26.29, 30.03, 29.02, 22.63, 39.21
Thrifty: 29.49, 12.19, 15.07, 15.17, 24.52, 22.32, 25.30, 22.74, 19.35, 34.44

A. Explain why this is a paired-sample problem.

B. Test (at a 0.05 significance level) with a t-test whether Thrifty has a lower true mean rental rate than Hertz. Make sure you state your hypotheses statements, test statistic value, p-value, and conclusions. Make sure to check assumptions. You may use R to compute the test statistic and p-value.

C. Compute a 90% confidence interval for the mean difference in price. Show all steps and interpret.

Answer 1