A number of airlines now charge a fee for booking a ticket directly with the airline either in person or by telephone. No fee is charged persons who book travel online. A survey conducted by SITA showed that in 2006, 47% of passengers booked their airline tickets online. In the 2007 this had increased to 49% and in 2008 to 57.6%.

a. Suppose the results are based on surveys of 2500 randomly selected passengers each year. At the .01 level of significance, is there evidence of a difference in the proportion of passengers who book tickets online among the three year groups?

Complete the following:
1. State H0.
2. State H1.
3. State the value of α.
4. State the value of the test statistic.
5. State the p-value.
6. State the decision in terms of H0 and why.
7. State the decision in terms of the problem.

b. If appropriate, use the Marascuilo procedure and α = .01 to determine which, if any, year groups are significantly different in the proportion of passengers who book tickets online.

c. Would the results change if samples of size 300 were used? Support your answer with appropriate calculations.