Keystones — Lintel
Five GCSE retrieval questions · 13 August 2026 · mathsvault.uk/keystones
-
1. Number Error intervals
A value is 40.6 (to dp). State the error interval
Answer: 40.55 ≤ x < 40.65 -
2. Algebra Expanding two brackets
Expand: (x - 2)(x - 3)
Answer: x² - 5x + 6 -
3. Geometry Area of a circle
Calculate the area of a circle with diameter 21cm
Answer: 346.36cm² -
4. Ratio One amount as a percentage of another
Express 27 as a percentage of 101
Answer: 26.73% -
5. Statistics Averages and range
Find the mean, median and range of: 35, 98, 41, 46, 41, 77, 13, 42, 23
Answer: Mean = 46.2, Median = 41, Range = 85