Two secretarial student, Joe and Ike, are used-Typewriter dealers. They found that the length of time before a major repair is required on Typewriter sold is normally distributed, with a mean equal to 11 months and a standard deviation of 2 months. If the dealers want only 5% of the typewriters to fail before the end of the guarantee period, for how many months should the typewriters be guaranteed?

Customers arrive at rich dunn's styling shop at a rate of 3 per hour, distributed in a poisson fashion. rich can perform an average of 5 haircuts per hour, according to a negative exponential distribution.a) the average number of customers waiting for haircuts= customersb) the average number of customers in the shop= customersc) the average time a customer waits until it is his or her turn= minutesd) the average time a customer spends in the shop= minutese) the percentage of time that rich is busy= percent