A company produces pens. The probability that any pen is defective is 0.08.
A sample of 15 pens is taken. Find the probability that 2 or more pens are defective.
An employee claims that the probability that a pen is defective is more than 0.08. They take a sample of 20 pens and 3 are defective. Stating your hypothesis clearly, test the employee's claim at the 5% significance level.
162 exam-style questions on AQA A Level Maths 2.5 O: Statistical hypothesis testing, covering 2.5.1 Language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, and 2.5.3 Hypothesis test for a Normal mean (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.