CAIE S2 2016 November — Question 7

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2016
SessionNovember
TopicPoisson Distribution
TypeJoint probability of separate processes

7 Men arrive at a clinic independently and at random, at a constant mean rate of 0.2 per minute. Women arrive at the same clinic independently and at random, at a constant mean rate of 0.3 per minute.
  1. Find the probability that at least 2 men and at least 3 women arrive at the clinic during a 5 -minute period.
  2. Find the probability that fewer than 36 people arrive at the clinic during a 1-hour period.