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S5 Mathematics: Permutations and Combinations Practice Paper 1

S5 Mathematics: Permutations and Combinations Practice Paper 1

  • 2026-11-03

S5 Mathematics: Permutations and Combinations Practice Paper 1

Set one separates ordered from unordered selections: full arrangements and C(5,2) first, then multi-role choices, mixed groups and the block method, then repeated letters and unlabelled groups, ending with the error of answering 15 instead of 30.

Quick answer 24, 10, 30, 6, 56, 30, 1 440, 280, 554 400 and 30.

01 Paper details (check answers afterwards)

Item Detail
Questions 10 questions
Suggested time 25 minutes
Difficulty mix Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1
Chapter Chapter: S5 Mathematics: Permutations and Combinations – Tutor Lesson Plan
Level S5

02 Questions (10 items)

  1. FoundationFour students stand in a line. How many different orders are possible?
  2. FoundationHow many ways are there to choose 2 books from 5 different books?
  3. FoundationFrom 6 people, pick a chairperson and a vice-chairperson who cannot be the same person. How many outcomes?
  4. FoundationHow many arrangements are there of the three letters A, B and C?
  5. IntermediateHow many 3-person teams can be formed from 8 students?
  6. IntermediateFrom 5 boys and 3 girls, choose 2 boys and 1 girl. How many combinations?
  7. IntermediateSeven people queue up with A and B standing next to each other. How many orders are possible?
  8. ChallengeNine people are split into three groups of 3, with the groups unlabelled. How many ways?
  9. ChallengeHow many distinct arrangements are there of all 11 letters in STATISTICS?
  10. Error redoFrom 6 people, choose 2 where one writes the report and one presents it. How many arrangements?

03 Answers and one-line notes

# Answer One-line note
1 24 orders Multiply 4 x 3 x 2 x 1, which is 4 factorial.
2 10 ways Order does not matter, so use C(5,2), which is 10.
3 30 outcomes That is 6 x 5, because the two roles are different.
4 6 arrangements It is 3 factorial, that is 3 x 2 x 1 = 6.
5 56 teams C(8,3) is 8 x 7 x 6 divided by 6, giving 56.
6 30 combinations Take C(5,2) times C(3,1), which is 10 x 3 = 30.
7 1 440 orders Treat A and B as one block so there are 6! orders, times 2 for swapping them, giving 1 440.
8 280 ways That is C(9,3) x C(6,3) x C(3,3) divided by 3!, which is 280.
9 554 400 arrangements Divide 11! by 3! x 3! x 2!, which is 39 916 800 divided by 72.
10 30 arrangements The roles differ, so order matters and the answer is 30, not the 15 of C(6,2).

04 What to do after marking

  • After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
  • Repeat the same item two days later; move to the next paper only when both attempts are correct.
  • Parents only need the answer and note columns; there is no need to explain every item.

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