Keystones — Lintel
Five GCSE retrieval questions · 1 October 2012 · mathsvault.uk/keystones
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1. Number Converting to standard form
Write 970,000 in standard form
Answer: 9.7 × 105 -
2. Algebra Factorising monic quadratics
Factorise: x² - 2x - 15
Answer: (x + 3)(x - 5) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 30cm, angle = 42°. Find opposite. Give your answer to 2 decimal places
Answer: 27.01cm -
4. Ratio Mixed ratio problems
Black and white counters are in the ratio 9:2. What fraction of the counters are white?
Answer: 2⁄11 -
5. Statistics Mean
The mean of 4 numbers is 33. If 3 of them are 31, 30, 40, what is the missing number?
Answer: 31