Keystones — Lintel
Five GCSE retrieval questions · 13 July 2025 · mathsvault.uk/keystones
-
1. Number Converting to standard form
0.0038
Answer: 3.8 × 10-3 -
2. Algebra Factorising monic quadratics
Factorise: x² - 12x + 36
Answer: (x - 6)(x - 6) -
3. Geometry SOHCAHTOA — missing length
Hypotenuse = 30cm, angle = 64°. Find adjacent side
Answer: 13.2cm -
4. Ratio Mixed ratio problems
Divide 180 in the ratio 4:1:1
Answer: 120, 30 and 30 -
5. Statistics Mean
The mean of 5 numbers is 25. If 4 of them are 49, 34, 30, 40, what is the missing number?
Answer: -28