CAIE S1 2008 June — Question 2

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2008
SessionJune
TopicConditional Probability
TypePerson selected from combined populations

2 In country \(A 30 \%\) of people who drink tea have sugar in it. In country \(B 65 \%\) of people who drink tea have sugar in it. There are 3 million people in country \(A\) who drink tea and 12 million people in country \(B\) who drink tea. A person is chosen at random from these 15 million people.
  1. Find the probability that the person chosen is from country \(A\).
  2. Find the probability that the person chosen does not have sugar in their tea.
  3. Given that the person chosen does not have sugar in their tea, find the probability that the person is from country \(B\).