Keystones — Lintel
Five GCSE retrieval questions · 4 December 2025 · mathsvault.uk/keystones
-
1. Number Converting to standard form
9900000
Answer: 9.9 × 106 -
2. Algebra Factorising monic quadratics
Factorise: x² + 4x - 21
Answer: (x + 7)(x - 3) -
3. Geometry SOHCAHTOA — missing length
Hypotenuse = 34cm, angle = 54°. Find adjacent side
Answer: 20cm -
4. Ratio Mixed ratio problems
Simplify: 9:6:15
Answer: 3:2:5 -
5. Statistics Mean
The mean of 4 numbers is 40. If 3 of them are 47, 19, 50, what is the missing number?
Answer: 44