CAIE S1 2018 November — Question 7

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2018
SessionNovember
TopicProbability Definitions
TypeTwo-way table probabilities

7 In a group of students, the numbers of boys and girls studying Art, Music and Drama are given in the following table. Each of these 160 students is studying exactly one of these subjects.
ArtMusicDrama
Boys244032
Girls151237
  1. Find the probability that a randomly chosen student is studying Music.
  2. Determine whether the events 'a randomly chosen student is a boy' and 'a randomly chosen student is studying Music' are independent, justifying your answer.
  3. Find the probability that a randomly chosen student is not studying Drama, given that the student is a girl.
  4. Three students are chosen at random. Find the probability that exactly 1 is studying Music and exactly 2 are boys.
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