Keystones — Cornerstone
Five GCSE retrieval questions · 23 March 2026 · mathsvault.uk/keystones
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1. Number Highest common factor
Find the HCF of 21 and 21
Answer: 3 -
2. Algebra Substitution
If x = 2, find the value of 4x + 8
Answer: 16 -
3. Geometry Circumference of a circle
Find the circumference of a circle with diameter 12cm
Answer: 37.7cm -
4. Ratio Percentage multipliers
What multiplier represents a 20% increase?
Answer: 1.2 -
5. Statistics Averages and range
Find the mean, mode, median and range of: 20, 40, 20, 22, 32
Answer: Mean = 26.8, Mode = 20, Median = 22, Range = 20