Leon wants to find an estimate for the number of fish in a lake.
He catches a sample of 40 fish in the lake and marks them with a safe dye. These fish are then released back into the lake.
The next week he catches a sample of 50 fish in the lake.
Leon finds that 8 of these fish are marked.
Work out an estimate for the number of fish in the lake.
Write down an assumption you have made.
20 exam-style questions on AQA GCSE Maths Capture Recapture. Each one has a worked solution and a mark scheme showing where the marks go.