In Example 4.12 we showed how to compute the probability of the number of boats arriving at a grain shipping dock in Churchill Manitoba using the Poisson probability distribution. In this example we compute the probability of a particular time interval between boat arrivals using the exponential probability distribution. In the previous problem we found that the mean number of arrivals was l = 2.5 per 6-hour period.

Now we want to compute the probability that a boat will arrive within 3 hours of the last boat arrival and also to compute the probability that a boat will arrive between 2 and 4 hours after the last arrival