5) An airline knows from experience that the distribution of the number of suitcases that get lost each week on a certain route is approximately normal with m = 15.5 and s = 3.6.

a) What is the probability that during a given week the airline will lose less than 20 suitcases?

Solution: Letbe the number of lost suitcases. We are looking for

b) What is the probability the airline will lose between 10 and 20 suitcases?

Solution: Now we are looking for