Keystones — Lintel
Five GCSE retrieval questions · 5 August 2025 · mathsvault.uk/keystones
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1. Number Converting to standard form
940000
Answer: 9.4 × 105 -
2. Algebra Factorising monic quadratics
Factorise: x² - 11x + 30
Answer: (x - 6)(x - 5) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 27cm, angle = 34°. Find opposite
Answer: 18.2cm -
4. Ratio Mixed ratio problems
Divide 145 in the ratio 2:2:1
Answer: 58, 58 and 29 -
5. Statistics Mean
The mean of 4 numbers is 21. If 3 of them are 26, 42, 42, what is the missing number?
Answer: -26