Computer Science · Oct / Nov 2025 · Paper 2 HL · Question 5

5. Ten children play a game in which all of them or none of them win a prize. The rules of the game are as follows: y 10 children are assigned a unique number from 0 to 9. y A cupboard contains 10 boxes, each numbered from 0 to 9. y 10 sheets of paper are numbered from 0 to 9. y One piece of paper is put into each box in random order (see Figure 4). Figure 4: 10 boxes, each containing a sheet of paper with a number from 0 to 9 Box 0 1 2 3 4 5 6 7 8 9 Paper 9 8 2 1 7 6 4 3 5 0 Each child is allowed to open 5 boxes to look for their own number. You can assume they will not open the same box twice. Child number 0 goes first and opens 5 of the 10 boxes.

Read automatically from the paper; the printed page above is exact.