Keystones — Lintel
Five GCSE retrieval questions · 16 December 2017 · mathsvault.uk/keystones
-
1. Number Converting to standard form
Write 0.000077 in standard form
Answer: 7.7 × 10-5 -
2. Algebra Factorising monic quadratics
Factorise: x² - 5x - 50
Answer: (x + 5)(x - 10) -
3. Geometry SOHCAHTOA — missing length
Adjacent = 27cm, angle = 57°. Find opposite. Give your answer to 2 decimal places
Answer: 41.58cm -
4. Ratio Mixed ratio problems
Simplify the ratio 2 hours : 35 minutes
Answer: 24:7 -
5. Statistics Mean
The mean of 5 numbers is 21. If 4 of them are 20, 20, 27, 17, what is the missing number?
Answer: 21