Chapter 18.2, Problem 14E

Percents of on-time arrivals for flights in the past two years were collected for 11 randomly selected airports. Data for these airports follow. Use α = .05 to test the hypothesis that there is no difference between the median percent of on-time arrivals for the two years. What is your conclusion?

	Percent On Time
Airport	Two Years Ago	Last Year
Boston Logan	71.78	69.69
Chicago O’Hare	68.23	65.88
Chicago Midway	77.98	78.40
Denver	78.71	75.78
Fort Lauderdale	77.59	73.45
Houston	77.67	78.68
Los Angeles	76.67	76.38
Miami	76.29	70.98
New York (JFK)	69.39	62.84
Orlando	79.91	76.49
Washington (Dulles)	75.55	72.42