CAIE S2 2009 November — Question 2

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2009
SessionNovember
TopicPoisson Distribution
TypeSingle period normal approximation

2 A computer user finds that unwanted emails arrive randomly at a uniform average rate of 1.27 per hour.
  1. Find the probability that more than 1 unwanted email arrives in a period of 5 hours.
  2. Find the probability that more than 850 unwanted emails arrive in a period of 700 hours.