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.
32 exam-style questions on WJEC A Level Maths 2.5.1 Statistical hypothesis testing. Each one has a worked solution and a mark scheme showing where the marks go.