Keystones — Capstone
Five GCSE retrieval questions · 15 January 2026 · mathsvault.uk/keystones
-
1. Number Rationalising the denominator
Rationalise: 5/√5
Answer: 5√5⁄5 -
2. Algebra Factorising non-monic quadratics
Factorise: 8x² -10x - 25
Answer: (2x - 5)(4x + 5) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 30cm, angle = 39°. Find opposite
Answer: 24.3cm -
4. Ratio Reverse percentages
A price of £844.80 includes a 20% increase. What was the price before the increase?
Answer: £704.00 -
5. Statistics Mean
The mean of 6 numbers is 32. If 5 of them are 47, 36, 32, 17, 44, what is the missing number?
Answer: 16