Halim has a numbered list of the 650 cars serviced by a garage last year. He wants a simple random sample of 30 of these cars, and he has a calculator that generates random integers.
Describe how Halim should select his sample.
Halim's sample contains 27 petrol cars and 3 diesel cars, although 20% of the 650 cars are diesel. Explain whether this means Halim's method was faulty.
28 exam-style questions on AQA A Level Maths 2.1 K: Statistical sampling, covering 2.1.1 Populations, samples and sampling techniques. Each one has a worked solution and a mark scheme showing where the marks go.