In the Arnold's Muffler example for the exponential distribution in this chapter, the average rate of service was given as 3 per hour, and the times were expressed in hours. Convert the average service rate to the number per minute and convert the times to minutes. Find the probabilities that the service times will be less than 1/2 hour, 1/3 hour, and 2/3 hour. Compare these probabilities to the probabilities found in the example.