Managers at a busy international airport are studying the times taken by arriving passengers to pass immigration, collect their luggage, then pass through customs. It is known that in the past this was 50 minutes. Some changes have been made to the queuing system in the hope of reducing this time. A random sample of 45 arriving passengers is taken and the rank sums calculated as P = 55, N = 410. Using a suitable approximation, test, with a 1% significance level, whether the median waiting time has reduced.