The 9 letters of the word RECORDERS are divided at random into two groups: a group of 5 letters and a group of 4 letters.

Mark scheme

Marking points from the official mark scheme (May/June 2024). The mark or mark type is shown in brackets.

1. [B1]
2. [B1] 7!/3! – e, xP4 – e, e a positive integer.
3. [M1] 5! / r!, f > 120, r = 1, 2
4. [A1] If no marks scored SC B1 for 840 – 120 = 720.
5. (B1) One of 5C3 × 4!, 5P3/3! ×4!, 4C1 × 5! or 5P2 ×4! seen.
6. (M1) a×4!+ b × 5! where a and b are integers between 1 and 10 inclusive, or c×4! + d×4! where c and d are integers between 1 and 20 inclusive.
7. (A1)
8. [B1] Correct no of ways for two correct identified scenarios other than three Rs two Es.
9. [M1] No of ways for five correct identified scenarios added or correct.
10. [M1] Accept evaluated, accept 9C4.
11. [A1]
12. (B1) One correct case evaluated accurately and linked with correct scenario.
13. (M1) No of ways for two correct scenarios added or correct.
14. (M1) Accept evaluated, accept 9C4.
15. (A1)
16. (B1) For one correct product unsimplified and linked with correct scenario.
17. (M1) For second correct product.
18. (M1) For adding probabilities of two correct scenarios or correct.
19. (A1)
20. (B1) Two correct probabilities linked with correct scenarios, accept unsimplified.
21. (M1) Four probabilities with denominators including a factor of 9x8x7x6 x n, where n is 1 or 5.
22. (M1) Probabilities of four correct scenarios added or correct.
23. (A1)