A business convention holds its registration on Wednesday morning from 9:00 A.M. to 12:00 noon. Past history has shown that registrant arrivals follow a Poisson distribution at an average rate of 432 per hour.
a) What is the probability that more than 450 registrants will arrive in an hour?
b) What is the probability that fewer than 400 registrants will arrive in an hour?
c) What is the probability that between 410 and 460 registrants will arrive in an hour?