Keystones — Lintel
Five GCSE retrieval questions · 30 December 2014 · mathsvault.uk/keystones
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1. Number Converting to standard form
Write 310,000,000 in standard form
Answer: 3.1 × 108 -
2. Algebra Factorising monic quadratics
Factorise: x² - x - 42
Answer: (x + 6)(x - 7) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 18cm, angle = 51°. Find opposite. Give your answer to 2 decimal places
Answer: 22.23cm -
4. Ratio Mixed ratio problems
Simplify the ratio m : 15cm
Answer: 20:3 -
5. Statistics Mean
The mean of 6 numbers is 27. If 5 of them are 27, 31, 26, 20, 30, what is the missing number?
Answer: 28