Bhavna has a bag containing a large number of beads.
She wants to find an estimate for the number of beads in the bag.
Bhavna takes a sample of 30 beads from the bag.
She marks each bead with a black cross.
She then puts the beads back in the bag.
Bhavna shakes the bag.
She now takes another sample of 30 beads from the bag.
4 of these beads have been marked with a black cross.
Work out an estimate for the total number of beads in the bag.
Write down any assumptions you have made.
Practise OCR GCSE Maths Capture Recapture with exam-style questions for Foundation and Higher tier. 20 questions, matched to the OCR GCSE Maths (J560) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
