Problem 3 A highway contractor order 10 road graders from a rental company. Records show that trouble-free operational time of a road grader has a mean time of 35 days with a standard deviation of 8.75 days. if the distribution of trouble-free operational time follows a gamma distribution, a. What is the probability that a road grader will be operational without a problem for 40 days? Hint: (18.3, 16) = 0.264 (0.736) b. If the rental company has an inventory of 50 graders and assuming that 10% will have a trouble-free operational life of less than 40 days, what is the probability of 2 out of the 10 ordered graders to have operational lives of less than 40 days? (0.021)