Keystones — Capstone
Five GCSE retrieval questions · 12 September 2026 · mathsvault.uk/keystones
-
1. Number Error intervals
95 is rounded to the nearest integer. What is the error interval?
Answer: 94.5 ≤ x < 95.5 -
2. Algebra Linear simultaneous equations
Solve: 2x + 3y = 41 and 3x - y = 23
Answer: x = 10, y = 7 -
3. Geometry Distance between two points
Find the distance between (1, -4) and (5, 7)
Answer: 11.7 -
4. Ratio Repeated percentage change
A car worth £16,903.00 depreciates by 12% each year for 4 years. What is it worth after 4 years?
Answer: £10,136.65 -
5. Statistics Expected frequency
A bag has 4 red out of 8 balls. If you pick 87 times (with replacement), how many times would you expect red?
Answer: 43.5