Keystones — Lintel
Five GCSE retrieval questions · 23 August 2010 · mathsvault.uk/keystones
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1. Number Converting to standard form
Write 70,000,000 in standard form
Answer: 7 × 107 -
2. Algebra Factorising monic quadratics
Factorise: x² - 4x - 45
Answer: (x + 5)(x - 9) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 28cm, angle = 32°. Find opposite. Give your answer to 2 decimal places
Answer: 17.5cm -
4. Ratio Mixed ratio problems
In ratio 12:1:2, what fraction is the second part?
Answer: 1⁄15 -
5. Statistics Mean
The mean of 6 numbers is 30. If 5 of them are 15, 18, 23, 25, 48, what is the missing number?
Answer: 51