Assume that during a given week that 190 of 220 arrivals of airline A are "on time." An arrival is considered on time if a plane arrives within 10 min of its scheduled arrival time. During the same...

Assume that during a given week that 190 of 220 arrivals of airline A are "on time." An arrival is considered on time if a

plane arrives within 10 min of its scheduled arrival time.

During the same week 82 of 99 arrivals of airline B are on time.

(a) Test the hypothesis that the proportions of on-time arrivals

are the same for both airlines (a= 0.05).

(b) Find a 95% confidence interval for PA – PB