Keystones — Capstone
Five GCSE retrieval questions · 29 October 2026 · mathsvault.uk/keystones
-
1. Number Error intervals
70 is rounded to the nearest integer. What is the error interval?
Answer: 69.5 ≤ x < 70.5 -
2. Algebra Linear simultaneous equations
Solve: 2x + 3y = 37 and 3x - y = 17
Answer: x = 8, y = 7 -
3. Geometry Distance between two points
Find the distance between (-2, -6) and (10, 3)
Answer: 15 -
4. Ratio Repeated percentage change
A car worth £9,683.00 depreciates by 23% each year for 5 years. What is it worth after 5 years?
Answer: £2,620.98 -
5. Statistics Expected frequency
A bag has 5 red out of 13 balls. If you pick 54 times (with replacement), how many times would you expect red?
Answer: 20.8