A lake contains five different types of fish.
There are an estimated 350 Roach, 250 Bream, 200 Rudd, 150 Tench and 450 Carp.
John wishes to investigate the health of the fish in the lake.
He decides to take a sample of k k\,k fish.
Give a reason why stratified random sampling cannot be used.
Explain how a sample of size k k\,k could be taken to ensure that the estimated populations of each type of fish are fairly represented.
You should state the name of the sampling method used and give the quota for each type of fish in terms of kkk.
59 exam-style questions on Edexcel A Level Maths Data Collection, covering 1.1 Populations and Samples, 1.2 Sampling, 1.3 Non-Random Sampling, 1.4 Types of Data, and 1.5 The Large Data Set. Each one has a worked solution and a mark scheme showing where the marks go.