Keystones — Capstone
Five GCSE retrieval questions · 31 October 2010 · mathsvault.uk/keystones
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1. Number Simplifying surds
Simplify: √162
Answer: 9√2 -
2. Algebra Completing the square
Complete the square: x² + 7x - 5
Answer: (x + 7⁄2)² - 69⁄4 -
3. Geometry Area using ½ab sin C
Find area of triangle: a = 21cm, b = 18cm, angle = 72°. Give your answer to 2 decimal places
Answer: 179.75cm² -
4. Ratio Combining two ratios
a:b is 5:7 and b:c is 9:2. Find a:b:c in its simplest form.
Answer: 45:63:14 -
5. Statistics Averages and range
Find the mean, median and range of: 55, 84, 25, 26, 27, 91, 47. Give your answer to 2 decimal places
Answer: Mean = 50.71, Median = 47, Range = 66