CAIE S2 2023 June — Question 4

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2023
SessionJune
TopicPoisson Distribution
TypeExplain or apply conditions in context

4 The number, \(X\), of books received at a charity shop has a constant mean of 5.1 per day.
  1. State, in context, one condition for \(X\) to be modelled by a Poisson distribution.
    Assume now that \(X\) can be modelled by a Poisson distribution.
  2. Find the probability that exactly 10 books are received in a 3-day period.
  3. Use a suitable approximating distribution to find the probability that more than 180 books are received in a 30-day period.
    The number of DVDs received at the same shop is modelled by an independent Poisson distribution with mean 2.5 per day.
  4. Find the probability that the total number of books and DVDs that are received at the shop in 1 day is more than 3 .