Keystones — Lintel
Five GCSE retrieval questions · 1 May 2010 · mathsvault.uk/keystones
-
1. Number Converting to standard form
Write 480,000 in standard form
Answer: 4.8 × 105 -
2. Algebra Factorising monic quadratics
Factorise: x² - 3x - 28
Answer: (x + 4)(x - 7) -
3. Geometry SOHCAHTOA — missing length
Hypotenuse = 23cm, angle = 40°. Find adjacent side. Give your answer to 2 decimal places
Answer: 17.62cm -
4. Ratio Mixed ratio problems
Red, blue and green marbles are in the ratio 2:2:9. What fraction of the marbles are green?
Answer: 9⁄13 -
5. Statistics Mean
The mean of 6 numbers is 29. If 5 of them are 20, 35, 21, 31, 38, what is the missing number?
Answer: 29