Keystones — Capstone
Five GCSE retrieval questions · 9 June 2026 · mathsvault.uk/keystones
-
1. Number Rationalising the denominator
Rationalise: 5/√5
Answer: 5√5⁄5 -
2. Algebra Factorising non-monic quadratics
Factorise: 8x² + 2x - 10
Answer: (2x - 2)(4x + 5) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 29cm, angle = 45°. Find opposite
Answer: 29cm -
4. Ratio Reverse percentages
A price of £755.20 includes a 28% increase. What was the price before the increase?
Answer: £590.00 -
5. Statistics Mean
The mean of 4 numbers is 36. If 3 of them are 15, 20, 18, what is the missing number?
Answer: 91