Edexcel S2 2009 June — Question 1

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2009
SessionJune
TopicApproximating the Binomial to the Poisson distribution
TypeCalculate single probability using Poisson approximation

  1. A bag contains a large number of counters of which \(15 \%\) are coloured red. A random sample of 30 counters is selected and the number of red counters is recorded.
    1. Find the probability of no more than 6 red counters in this sample.
    A second random sample of 30 counters is selected and the number of red counters is recorded.
  2. Using a Poisson approximation, estimate the probability that the total number of red counters in the combined sample of size 60 is less than 13.