Year 8 Circumference and Area of Circles Worksheet — Level 2 — 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 — Answers
Show your working. Use the π button on your calculator and round to 1 decimal place unless told otherwise.
1.A circle has a radius of 15 cm. Find its area, correct to 1 decimal place.
Answer: 706.9 cm2
- A = π × r2 = π × 152 = π × 225
- ≈ 706.9 cm2
2.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
3.A circle has a diameter of 40 cm. Find its area, correct to 1 decimal place.
Answer: 1256.6 cm2
- r = 40 ÷ 2 = 20 cm
- A = π × r2 = π × 202 = π × 400
- ≈ 1256.6 cm2
4.A circle has a diameter of 30 cm. Find its circumference, correct to 1 decimal place.
Answer: 94.2 cm
- C = π × d = π × 30
- ≈ 94.2 cm
5.Find the area of a semicircle with a radius of 15 cm, correct to 1 decimal place.
Answer: 353.4 cm2
- A = ½ × π × r2 = ½ × π × 225
- ≈ 353.4 cm2
6.A circle has a diameter of 26 cm. Find its circumference, correct to 1 decimal place.
Answer: 81.7 cm
- C = π × d = π × 26
- ≈ 81.7 cm
7.A circle has a diameter of 34 cm. Find its area, correct to 1 decimal place.
Answer: 907.9 cm2
- r = 34 ÷ 2 = 17 cm
- A = π × r2 = π × 172 = π × 289
- ≈ 907.9 cm2
8.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
9.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
10.Find the area of a semicircle with a radius of 10 cm, correct to 1 decimal place.
Answer: 157.1 cm2
- A = ½ × π × r2 = ½ × π × 100
- ≈ 157.1 cm2
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