Edexcel S2 — Question 2

Exam BoardEdexcel
ModuleS2 (Statistics 2)
TopicPoisson Distribution
TypeFinding minimum stock level for demand

2. The number of copies of The Statistician that a newsagent sells each week is modelled by a Poisson distribution. On average, he sells 1.5 copies per week.
  1. Find the probability that he sells no copies in a particular week.
  2. If he stocks 5 copies each week, find the probability he will not have enough copies to meet that week's demand.
  3. Find the minimum number of copies that he should stock in order to have at least a \(95 \%\) probability of being able to satisfy the week's demand.