Four-week summer rainfall totals, in inches, in a section of the Midwestern United States have approximately a gamma distribution with α = 1.8 and β = 5.
(a) Find the mean, in inches, and variance of the four-week rainfall totals.
E(X) = 9 inches
V(X) = 45 inches
(b) What is the probability that the four-week rainfall total exceeds 7 inches? (Round your answer to four decimal places.)