Year 9 Circumference and Area of Circles Worksheet — Level 2 — Practice Set 3 — 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 — Practice Set 3 — 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 11 cm, correct to 1 decimal place.
Answer: 190.1 cm2
- A = ½ × π × r2 = ½ × π × 121
- ≈ 190.1 cm2
2.A circle has a radius of 6 cm. Find its area, correct to 1 decimal place.
Answer: 113.1 cm2
- A = π × r2 = π × 62 = π × 36
- ≈ 113.1 cm2
3.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
4.A circle has a diameter of 18 cm. Find its circumference, correct to 1 decimal place.
Answer: 56.5 cm
- C = π × d = π × 18
- ≈ 56.5 cm
5.A circle has a radius of 14 cm. Find its area, correct to 1 decimal place.
Answer: 615.8 cm2
- A = π × r2 = π × 142 = π × 196
- ≈ 615.8 cm2
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 radius of 18 cm. Find its area, correct to 1 decimal place.
Answer: 1017.9 cm2
- A = π × r2 = π × 182 = π × 324
- ≈ 1017.9 cm2
8.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
9.A circle has a radius of 15 cm. Find its circumference, correct to 1 decimal place.
Answer: 94.2 cm
- C = 2 × π × r = 2 × π × 15
- ≈ 94.2 cm
10.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
Marking tips
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