GCSE · Sampling

Bias & sampling methodsExam-style questions

What bias really is — a method that systematically leaves people out, so a bigger sample never fixes it — how to name who is missing, the strengths and weaknesses of random, systematic, stratified and convenience sampling, and how to criticise and rewrite a questionnaire.

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11 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAll Level 1 Level 2 Level 3 Level 4 Level 5

1
Priya wants to find out how much time students at her school spend on homework each week. She asks the 20 students in her own maths class.

(a) Write down the type of sample Priya has taken.

(b) Explain why her sample may be biased.
Level 2 · 2 marksTry it
2
Describe how to choose a random sample of $20$ students from a year group of $200$ .
Level 2 · 2 marksTry it