Leo wants to estimate the number of fish in a small lake.
He catches a sample of 40 fish from the lake. He marks each fish with a tag and releases them back into the lake.
The next day, Leo catches another sample of 50 fish from the lake. He finds that 5 of these fish have tags.
Work out an estimate for the total number of fish in the lake.
Write down any assumptions you have made.
20 exam-style questions on Edexcel GCSE Maths Capture Recapture. Each one has a worked solution and a mark scheme showing where the marks go.