Suppose the number of phone calls arriving at a switchboard per hour is Poisson
Chapter 12, Problem 86(choose chapter or problem)
Suppose the number of phone calls arriving at a switchboard per hour is Poisson distributed with mean 3 calls per hour. (a) Find the probability that at least one phone call arrives between noon and 1 P.M. (b) Assuming that phone calls in different hours are independent of each other, find the probability that no phone calls arrive between noon and 2 P.M.
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