Keystones — Lintel
Five GCSE retrieval questions · 9 May 2026 · mathsvault.uk/keystones
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1. Number Error intervals
A value is 59.2 (to dp). State the error interval
Answer: 59.15 ≤ x < 59.25 -
2. Algebra Expanding two brackets
Expand: (x + 6)(x - 8)
Answer: x² -2x - 48 -
3. Geometry Area of a circle
A circle has area 113.cm². Find its radius (dp)
Answer: 6cm -
4. Ratio One amount as a percentage of another
Express 56 as a percentage of 250
Answer: 22.4% -
5. Statistics Averages and range
Find the mean, median and range of: 97, 56, 75, 89, 49, 30, 52, 75
Answer: Mean = 65.4, Median = 75, Range = 67