It is known that 17% of the cars serviced at a garage need a new air filter. The manager believes that this proportion has increased since a change of supplier.
A random sample of 60 cars serviced since the change is taken, and 16 of them need a new air filter.
Stating your hypotheses clearly, test the manager's belief at the 2.5% significance level.
State, with a reason, the conclusion you would have reached at the 5% significance level.
40 exam-style questions on WJEC A Level Maths 2.5 Statistical hypothesis testing, covering 2.5.1 Statistical hypothesis testing, 2.5.2 Statistical hypothesis testing, 2.5.3 Statistical hypothesis testing, 2.5.4 Statistical hypothesis testing, and 2.5 Statistical hypothesis testing. Each one has a worked solution and a mark scheme showing where the marks go.