GCSE · Sampling

Populations & samplesExam-style questions

What a population and a sample are and why we sample at all; why a representative sample matters more than a big one; and the two calculations that earn the marks — scaling a sample up to estimate a population total (including capture–recapture and its assumptions) and sharing a stratified sample out in proportion.

Start practising Read the lesson

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
A wildlife group is estimating the number of deer in a large forest.

They catch $32$ deer, fit each one with a tag and release them.

Two weeks later they catch $48$ deer. $12$ of these deer have a tag.

(a) Work out an estimate for the number of deer in the forest.

(b) State one assumption you have made in working out your estimate.
Level 4 · 4 marksTry it
2
A college has $500$ students.
Group Number of students
Year 12 $236$
Year 13 $153$
Adult learners $111$
Rosa takes a stratified sample of $25$ of these students.

Work out how many students from each group should be in Rosa's sample.

You must show that your three numbers add up to $25$ .
Level 4 · 4 marksTry it

Group	Number of students
Year 12	$236$
Year 13	$153$
Adult learners	$111$