Question: The time (in minutes) between telephone calls at an insurance claims office has the following exponential probability distribution.
f(x) = .50e-.50x for x ≥ 0
a. What is the mean time between telephone calls?
b. What is the probability of having 30 seconds or less between telephone calls?
c. What is the probability of having I minute or less between telephone calls?
d. What is the probability of having 5 or more minutes without a telephone call?