Keystones — Capstone
Five GCSE retrieval questions · 7 September 2026 · mathsvault.uk/keystones
-
1. Number Error intervals
65 is rounded to the nearest integer. What is the error interval?
Answer: 64.5 ≤ x < 65.5 -
2. Algebra Linear simultaneous equations
Solve: 2x + 3y = 34 and 3x - y = 18
Answer: x = 8, y = 6 -
3. Geometry Distance between two points
Find the distance between (-6, -6) and (8, 4)
Answer: 17.2 -
4. Ratio Repeated percentage change
A car worth £7,083.00 depreciates by 18% each year for 5 years. What is it worth after 5 years?
Answer: £2,625.95 -
5. Statistics Expected frequency
A bag has 3 red out of 12 balls. If you pick 57 times (with replacement), how many times would you expect red?
Answer: 14.3