Year 9 Circumference and Area of Circles Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the Year 9 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Area & PerimeterYear 9 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 diameter of 40 cm. Find its circumference, correct to 1 decimal place.
Answer: 125.7 cm
- C = π × d = π × 40
- ≈ 125.7 cm
2.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
3.A circle has a radius of 17 cm. Find its area, correct to 1 decimal place.
Answer: 907.9 cm2
- A = π × r2 = π × 172 = π × 289
- ≈ 907.9 cm2
4.A circle has a diameter of 14 cm. Find its circumference, correct to 1 decimal place.
Answer: 44.0 cm
- C = π × d = π × 14
- ≈ 44.0 cm
5.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
6.A circle has a diameter of 34 cm. Find its circumference, correct to 1 decimal place.
Answer: 106.8 cm
- C = π × d = π × 34
- ≈ 106.8 cm
7.A circle has a diameter of 24 cm. Find its area, correct to 1 decimal place.
Answer: 452.4 cm2
- r = 24 ÷ 2 = 12 cm
- A = π × r2 = π × 122 = π × 144
- ≈ 452.4 cm2
8.Find the area of a semicircle with a radius of 19 cm, correct to 1 decimal place.
Answer: 567.1 cm2
- A = ½ × π × r2 = ½ × π × 361
- ≈ 567.1 cm2
9.A circle has a diameter of 8 cm. Find its area, correct to 1 decimal place.
Answer: 50.3 cm2
- r = 8 ÷ 2 = 4 cm
- A = π × r2 = π × 42 = π × 16
- ≈ 50.3 cm2
10.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
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