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 120 fish.
Give a reason why stratified random sampling cannot be used.
Explain how a sample of size 120 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.
Practise Edexcel AS Level Maths Data Collection with exam-style questions for AS Level Maths. 4 questions covering Populations and Samples, Sampling, Non-Random Sampling, Types of Data, and The Large Data Set, matched to the Edexcel AS Level Maths (8MA0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.