Keystones — Lintel
Five GCSE retrieval questions · 25 January 2014 · mathsvault.uk/keystones
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1. Number Converting to standard form
Write 78,000,000 in standard form
Answer: 7.8 × 107 -
2. Algebra Factorising monic quadratics
Factorise: x² - 7x - 30
Answer: (x + 3)(x - 10) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 30cm, angle = 35°. Find opposite. Give your answer to 2 decimal places
Answer: 21.01cm -
4. Ratio Mixed ratio problems
Divide 147 in the ratio 2:2:3
Answer: 42, 42 and 63 -
5. Statistics Mean
The mean of 4 numbers is 28. If 3 of them are 36, 15, 31, what is the missing number?
Answer: 30