A sixth form college has 72 students in Year 12 and 63 students in Year 13.
The head teacher selects a stratified sample of 30 students, stratified by year group.
Describe how this sample could be taken, and hence state the fraction of the sample that should be from Year 12.
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.