The number of telephone calls that arrive at a phone exchange is often modeled as a poisson random variable. assume that on average there are 10 calls per hour,
a) What is the probability that there are exactly 5 calls in one hour?
b) What is the probability that there are 3 or fewer calls in one hour?
c) What is the probability that there are exactly 15 calls in tow hours?
d) What is the probability that there are exactly 5 calls in 30 minutes?