Keystones — Lintel
Five GCSE retrieval questions · 2 August 2010 · mathsvault.uk/keystones
-
1. Number Converting to standard form
Write 85,000,000 in standard form
Answer: 8.5 × 107 -
2. Algebra Factorising monic quadratics
Factorise: x² - 3x - 108
Answer: (x + 9)(x - 12) -
3. Geometry SOHCAHTOA — missing length
Hypotenuse = 16cm, angle = 60°. Find adjacent side
Answer: 8cm -
4. Ratio Mixed ratio problems
Orange, purple and pink beads are in the ratio 3:3:1. What fraction of the beads are purple?
Answer: 3⁄7 -
5. Statistics Mean
The mean of 5 numbers is 30. If 4 of them are 20, 39, 38, 43, what is the missing number?
Answer: 10