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 flights, since they tend to need the most flexibility and w ant to be home on weekends. Eight months ago, the overnight stay requirements were as follows:
a. Specify the competing hypotheses to test whether the recent proportions differ from those cited in the study.
b. Calculate the value of the test statistic.
c. At a 5% significance level, what is the critical value?
d. What is the conclusion to the hypothesis test? Interpret your results.