Edexcel S2 — Question 3

Exam BoardEdexcel
ModuleS2 (Statistics 2)
TopicPoisson Distribution
TypeExplain or apply conditions in context

3. An electrician records the number of repairs of different types of appliances that he makes each day. His records show that over 40 working days he repaired a total of 180 CD players.
  1. Explain why a Poisson distribution may be suitable for modelling the number of CD players he repairs each day and find the parameter for this distribution.
  2. Find the probability that on one particular day he repairs
    1. no CD players,
    2. more than 6 CD players.
  3. Find the probability that over 10 working days he will repair more than 6 CD players on exactly 3 of the days.
    (3 marks)