Keystones — Capstone
Five GCSE retrieval questions · 1 September 2015 · mathsvault.uk/keystones
-
1. Number Simplifying surds
Simplify: √525
Answer: 5√21 -
2. Algebra Completing the square
Complete the square: x² - x - 1
Answer: (x - 1⁄2)² - 5⁄4 -
3. Geometry Area using ½ab sin C
Find area of triangle: a = 21cm, b = 23cm, angle = 75°. Give your answer to 2 decimal places
Answer: 233.27cm² -
4. Ratio Combining two ratios
a:b is 5:3 and b:c is 2:1. Find a:b:c in its simplest form.
Answer: 10:6:3 -
5. Statistics Averages and range
Find the mean, median and range of: 93, 34, 51, 49, 62, 43, 99, 84, 69. Give your answer to 2 decimal places
Answer: Mean = 64.89, Median = 62, Range = 65