As reported by Runner's World magazine, the times of the finishers in the New York City 10-km run are normally distributed with a mean of 61 minutes and a standard deviation of 9 minutes. Let x be the finishing time for a finisher in the New York 10-km run.
a) What is the chance that finishers complete the run with the times between 50 and 70 minutes?
b) What is the chance that finishers complete the run with the times more than 75 minutes?
c) How fast would finishers have to complete the run among the top 5% finishers?
On average, 70 percent of the passengers on a flight from San Francisco to Boston prefer chicken to fish. Assume that the passengers have only one of two choices, chicken or fish for their meal. If there are 200 passengers on a flight and the airline carries 140 chickens and 60 fish dinners, what is the probability that more than five passengers will be disappointed?