A study suggests that airlines have increased restrictions on cheap fares by raising overnight requirements (The Wall Street Journal, August 19, 2008). This would force business travelers to pay more for their lights, since they tend to need the most flexibility and want to be home on weekends. Eight months ago, the overnight stay requirements were as follows:

A recent sample of 644 lights found the following restrictions:

a. Specify the competing hypotheses to test whether the recent proportions differ from those cited in the study.

b. At the 5% significance level, find the critical value.

c. Calculate the value of the test statistic.

d. What is the conclusion to the hypothesis test? Interpret your results.

One night 37% Two nights Three nights Saturday night 18% 17% 28%