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 2 cm, correct to 1 decimal place.
Answer: 6.3 cm2
- A = ½ × π × r2 = ½ × π × 4
- ≈ 6.3 cm2
2.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
3.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
4.Find the area of a semicircle with a radius of 18 cm, correct to 1 decimal place.
Answer: 508.9 cm2
- A = ½ × π × r2 = ½ × π × 324
- ≈ 508.9 cm2
5.A circle has a diameter of 36 cm. Find its circumference, correct to 1 decimal place.
Answer: 113.1 cm
- C = π × d = π × 36
- ≈ 113.1 cm
6.A circle has a radius of 7 cm. Find its circumference, correct to 1 decimal place.
Answer: 44.0 cm
- C = 2 × π × r = 2 × π × 7
- ≈ 44.0 cm
7.A circle has a diameter of 32 cm. Find its circumference, correct to 1 decimal place.
Answer: 100.5 cm
- C = π × d = π × 32
- ≈ 100.5 cm
8.Find the area of a semicircle with a radius of 12 cm, correct to 1 decimal place.
Answer: 226.2 cm2
- A = ½ × π × r2 = ½ × π × 144
- ≈ 226.2 cm2
9.Find the area of a semicircle with a radius of 5 cm, correct to 1 decimal place.
Answer: 39.3 cm2
- A = ½ × π × r2 = ½ × π × 25
- ≈ 39.3 cm2
10.A circle has a radius of 5 cm. Find its circumference, correct to 1 decimal place.
Answer: 31.4 cm
- C = 2 × π × r = 2 × π × 5
- ≈ 31.4 cm
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