Keystones — Lintel
Five GCSE retrieval questions · 20 November 2014 · mathsvault.uk/keystones
-
1. Number Converting to standard form
Write 0.000023 in standard form
Answer: 2.3 × 10-5 -
2. Algebra Factorising monic quadratics
Factorise: x² - 13x + 40
Answer: (x - 5)(x - 8) -
3. Geometry SOHCAHTOA — missing length
Hypotenuse = 24cm, angle = 55°. Find adjacent side. Give your answer to 2 decimal places
Answer: 13.77cm -
4. Ratio Mixed ratio problems
Black, white and yellow marbles are in the ratio 9:5:9. What fraction of the marbles are yellow?
Answer: 9⁄23 -
5. Statistics Mean
The mean of 5 numbers is 30. If 4 of them are 26, 37, 46, 31, what is the missing number?
Answer: 10