Keystones — Capstone
Five GCSE retrieval questions · 12 January 2026 · mathsvault.uk/keystones
-
1. Number Rationalising the denominator
Rationalise: 4/√3
Answer: 4√3⁄3 -
2. Algebra Factorising non-monic quadratics
Factorise: 9x² -3x - 20
Answer: (3x - 5)(3x + 4) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 17cm, angle = 58°. Find opposite
Answer: 27.2cm -
4. Ratio Reverse percentages
A price of £270.60 includes a 23% increase. What was the price before the increase?
Answer: £220.00 -
5. Statistics Mean
The mean of 5 numbers is 35. If 4 of them are 36, 43, 43, 38, what is the missing number?
Answer: 15