Toyota company prides themselves on customer service. they havebeen trying to determine exactly how long it takes, from start tofinish, to buy a car at their dealerships. they have determinedthat the two parts of the transaction (showroom and service) followthe normal model. showroom has a mean time of 3.5 hours with astandard deviation of 1.5 hours. service has an average time of 2hours with a standard deviation of 0.5 hours.
a) What is the mean and standard deviation of the differencebetween the showroom and service average waiting time.
b) What is the probability that it will take a customer longerduring the service portion of the transaction.
c) Why does the standard deviation always increase when we addor subtract the means of two distributions.
