Lemmara logoLemmaraWorked solution

4024/12 Oct/Nov 2025, Question 19: Fractional Indices

Cambridge O Level Mathematics 4024 · Paper 12 (Non-calculator) · Non-calculator · 4 marks

اقرأ هذا الحل مشروحاً بالعربي ←

The question, in short

Evaluate 16^(−3/4) and express 9² × 3^(−1/2) as a single power of 3.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (a) · 2 marks

Find the value of 16 raised to the power −3/4.

  1. 116^(1/4) = 2, so 16^(3/4) = 2³ = 8
  2. 216^(−3/4) = 1/8

Answer1/8

Part (b) · 2 marks

Rewrite 9² × 3^(−1/2) as one power of 3.

  1. 19² = (3²)² = 3⁴
  2. 23⁴ × 3^(−1/2) = 3^(4 − 1/2)
  3. 3= 3^(7/2)

Answer3^(7/2)

Stuck on a step? Read the free lesson: Fractional Indices

Practise more fractional indices questions

Real 4024 past-paper questions, marked on your working like the exam, with a worked solution for every part.

Practise free on Lemmara

More past-paper questions on fractional indices

Also searched as: 4024/12/O/N/25 · 4024_w25_qp_12 · 4024 w25 12 · question 19.
Lemmara is an independent study tool, not affiliated with or endorsed by Cambridge International Education. The worked solutions are Lemmara’s own.