Skip to main content
A-LevelMathematicsProbability and statistics9709/62 · Oct/Nov 2018 · Q46 Marks

Find the number of different ways that 5 boys and 6 girls can stand in a row if all the boys stand together and all the girls stand together.

  1. (i)Find the number of different ways that 5 boys and 6 girls can stand in a row if all the boys stand together and all the girls stand together.[3]
  2. (ii)Find the number of different ways that 5 boys and 6 girls can stand in a row if no boy stands next to another boy.[3]

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2018). The mark or mark type is shown in brackets.

  1. [B1] k×5! or m×6! (k,m integer, k,m ≥ 1), no inappropriate addition
  2. [B1] n × 5! × 6! (n integer, n ≥ 1), no inappropriate addition
  3. [B1] Correct final answer, isw rounding (www scores B3) All marks based on their final answer
  4. [M1] k× 6! or k × ⁷P₅ (k is an integer, k ≥ 1) no inappropriate add. (⁷P₅ = 7 × 6 × 5 × 4 × 3 or ⁷C₅ × 5!)
  5. [M1] Correct unsimplified expression
  6. [A1] Correct exact final answer (ignore subsequent rounding)

Write your answer and get it marked

On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.

Sign up free →

About this question

Topic
Probability and statistics, A-Level Mathematics (syllabus 9709). Structured question, 6 marks.
Source
A-Level Mathematics, Oct/Nov 2018 Paper 6 Variant 2, question 4.

Questions and mark schemes are from past examination papers and remain the copyright of the exam board. How Oracle Prep builds its content

Related Mathematics questions

© 2026 Oracle Prep