CAIE Further Paper 4 2022 November — Question 2

Exam BoardCAIE
ModuleFurther Paper 4 (Further Paper 4)
Year2022
SessionNovember
TopicChi-squared distribution

2 An organisation runs courses to train students to become engineers. These students are taught in groups of 8 . The director of the organisation claims that on average \(60 \%\) of the students in a group achieve a pass. A random sample of 150 groups of 8 students is chosen. The following table shows the observed frequencies together with some of the expected frequencies using the appropriate binomial distribution.
Number of passes per group012345678
Observed frequency00824453626101
Expected frequency\(p\)1.1806.19318.57934.836\(q\)\(r\)13.4372.519
  1. Find the values of \(p , q\) and \(r\) giving your answers correct to 3 decimal places.
  2. Carry out a goodness of fit test, at the \(10 \%\) significance level, to test whether there is evidence to reject the director's claim.