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.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
2.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
3.Find the area of a semicircle with a radius of 14 cm, correct to 1 decimal place.
Answer: 307.9 cm2
- A = ½ × π × r2 = ½ × π × 196
- ≈ 307.9 cm2
4.A circle has a diameter of 12 cm. Find its circumference, correct to 1 decimal place.
Answer: 37.7 cm
- C = π × d = π × 12
- ≈ 37.7 cm
5.A circle has a diameter of 24 cm. Find its circumference, correct to 1 decimal place.
Answer: 75.4 cm
- C = π × d = π × 24
- ≈ 75.4 cm
6.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
7.A circle has a radius of 18 cm. Find its circumference, correct to 1 decimal place.
Answer: 113.1 cm
- C = 2 × π × r = 2 × π × 18
- ≈ 113.1 cm
8.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
9.A circle has a diameter of 36 cm. Find its area, correct to 1 decimal place.
Answer: 1017.9 cm2
- r = 36 ÷ 2 = 18 cm
- A = π × r2 = π × 182 = π × 324
- ≈ 1017.9 cm2
10.A circle has a radius of 10 cm. Find its area, correct to 1 decimal place.
Answer: 314.2 cm2
- A = π × r2 = π × 102 = π × 100
- ≈ 314.2 cm2
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