CAIE S1 2023 November — Question 5

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2023
SessionNovember
TopicConditional Probability
TypeProbability distribution from conditional setup

5 A red spinner has four sides labelled \(1,2,3,4\). When the spinner is spun, the score is the number on the side on which it lands. The random variable \(X\) denotes this score. The probability distribution table for \(X\) is given below.
\(x\)1234
\(\mathrm { P } ( X = x )\)0.28\(p\)\(2 p\)\(3 p\)
  1. Show that \(p = 0.12\).
    A fair blue spinner and a fair green spinner each have four sides labelled 1, 2, 3, 4. All three spinners (red, blue and green) are spun at the same time.
  2. Find the probability that the sum of the three scores is 4 or less.
  3. Find the probability that the product of the three scores is 4 or less given that \(X\) is odd.