Mathematics (AS & A Level) · May / June 2016 · Paper 72 · Question 2

Jacques is a chef. He claims that 90% of his customers are satisfied with his cooking. Marie suspects that the true percentage is lower than 90%. She asks a random sample of 15 of Jacques’ customers whether they are satisfied. She then performs a hypothesis test of the null hypothesis p = 0.9 against the alternative hypothesis p < 0.9, where p is the population proportion of customers who are satisfied. She decides to reject the null hypothesis if fewer than 12 customers are satisfied.

Read automatically from the paper; the printed page above is exact.