Keystones — Lintel
Five GCSE retrieval questions · 22 November 2010 · mathsvault.uk/keystones
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1. Number Converting to standard form
Write 480,000,000 in standard form
Answer: 4.8 × 108 -
2. Algebra Factorising monic quadratics
Factorise: x² - 6x - 27
Answer: (x + 3)(x - 9) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 20cm, angle = 32°. Find opposite. Give your answer to 2 decimal places
Answer: 12.5cm -
4. Ratio Mixed ratio problems
Red and blue sweets are in the ratio 5:14. What fraction of the sweets are blue?
Answer: 14⁄19 -
5. Statistics Mean
The mean of 5 numbers is 24. If 4 of them are 19, 19, 18, 50, what is the missing number?
Answer: 14