4MA1/2H Jan 2021, Question 8: Composite Perimeter, Area and Volume
Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 2H (Higher) · Calculator · 5 marks
اقرأ هذا الحل مشروحاً بالعربي ←
The question, in short
Using a circle with diameter AOC and right-angled triangle ABC inside it, where AB = 8 cm and BC = 15 cm, find the total shaded area outside the triangle, to 3 significant figures.
Summarised in our own words. Use the official paper for the exact wording and the diagram.
Solution · 5 marks
- 1Angle ABC = 90°, so use Pythagoras in triangle ABC: AC² = 8² + 15²
- 28² + 15² = 64 + 225 = 289, so AC = 17 cm
- 3AC is a diameter, so the radius is 17 ÷ 2 = 8.5 cm
- 4Circle area = π × 8.5² = 226.98 cm²
- 5Triangle area = 0.5 × 8 × 15 = 60 cm²
- 6Shaded area = 226.98 − 60 = 166.98
- 7To 3 significant figures that is 167 cm²
Answer167
Stuck on a step? Read the free lesson: Composite Perimeter, Area and Volume
Practise more composite perimeter, area and volume questions
Real 4MA1 past-paper questions, marked on your working like the exam, with a worked solution for every part.
Practise free on LemmaraMore past-paper questions on composite perimeter, area and volume
Also searched as: 4MA1 2H January 2021 · 4MA1/2H · 4ma1 jan21 2h · question 8.
Lemmara is an independent study tool, not affiliated with or endorsed by Pearson Edexcel. The worked solutions are Lemmara’s own.