Year 8 Circumference and Area of Circles Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Area & PerimeterYear 8 Circumference and Area of Circles Worksheet — Level 2 — Practice Set 4 — Answers
Show your working. Use the π button on your calculator and round to 1 decimal place unless told otherwise.
1.Find the area of a semicircle with a radius of 20 cm, correct to 1 decimal place.
Answer: 628.3 cm2
- A = ½ × π × r2 = ½ × π × 400
- ≈ 628.3 cm2
2.A circle has a diameter of 32 cm. Find its area, correct to 1 decimal place.
Answer: 804.2 cm2
- r = 32 ÷ 2 = 16 cm
- A = π × r2 = π × 162 = π × 256
- ≈ 804.2 cm2
3.A circle has a radius of 9 cm. Find its area, correct to 1 decimal place.
Answer: 254.5 cm2
- A = π × r2 = π × 92 = π × 81
- ≈ 254.5 cm2
4.A circle has a radius of 8 cm. Find its area, correct to 1 decimal place.
Answer: 201.1 cm2
- A = π × r2 = π × 82 = π × 64
- ≈ 201.1 cm2
5.A circle has a radius of 3 cm. Find its area, correct to 1 decimal place.
Answer: 28.3 cm2
- A = π × r2 = π × 32 = π × 9
- ≈ 28.3 cm2
6.Find the area of a semicircle with a radius of 9 cm, correct to 1 decimal place.
Answer: 127.2 cm2
- A = ½ × π × r2 = ½ × π × 81
- ≈ 127.2 cm2
7.Find the area of a semicircle with a radius of 8 cm, correct to 1 decimal place.
Answer: 100.5 cm2
- A = ½ × π × r2 = ½ × π × 64
- ≈ 100.5 cm2
8.A circle has a radius of 13 cm. Find its circumference, correct to 1 decimal place.
Answer: 81.7 cm
- C = 2 × π × r = 2 × π × 13
- ≈ 81.7 cm
9.A circle has a radius of 17 cm. Find its circumference, correct to 1 decimal place.
Answer: 106.8 cm
- C = 2 × π × r = 2 × π × 17
- ≈ 106.8 cm
10.A circle has a diameter of 22 cm. Find its circumference, correct to 1 decimal place.
Answer: 69.1 cm
- C = π × d = π × 22
- ≈ 69.1 cm
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