Edexcel S2 2016 October — Question 7

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2016
SessionOctober
TopicDiscrete Random Variables
TypeSampling distribution of mean or linear combination

  1. An ice cream shop sells a large number of 1 scoop, 2 scoop and 3 scoop ice cream cones to its customers in the ratio \(5 : 2 : 1\)
A random sample of 2 customers at the ice cream shop is taken. Each customer orders a 1 scoop or a 2 scoop or a 3 scoop ice cream cone. Let \(S\) represent the total number of ice cream scoops ordered by these 2 customers.
  1. Find the sampling distribution of \(S\) A random sample of \(n\) customers at the ice cream shop is taken. Each customer orders a 1 scoop or a 2 scoop or a 3 scoop ice cream cone. The probability that more than \(n\) scoops of ice cream are ordered by these customers is greater than 0.99
  2. Find the smallest possible value of \(n\)
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