Keystones — Capstone
Five GCSE retrieval questions · 25 October 2015 · mathsvault.uk/keystones
-
1. Number Simplifying surds
Simplify: 3√50
Answer: 15√2 -
2. Algebra Completing the square
Complete the square: x² + 5x - 11
Answer: (x + 5⁄2)² - 69⁄4 -
3. Geometry Area using ½ab sin C
Find area of triangle: a = 17cm, b = 16cm, angle = 55°. Give your answer to 2 decimal places
Answer: 111.4cm² -
4. Ratio Combining two ratios
a:b is 7:5 and b:c is 4:7. Find a:b:c in its simplest form.
Answer: 28:20:35 -
5. Statistics Averages and range
Find the mean, median and range of: 78, 90, 20, 20, 24, 42, 77. Give your answer to 2 decimal places
Answer: Mean = 50.14, Median = 42, Range = 70