Year 8 Circumference and Area of Circles Worksheet — Level 1 — Practice Set 3 — 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 1 — Practice Set 3 — 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 6 cm. Find its circumference, correct to 1 decimal place.
Answer: 37.7 cm
- C = 2 × π × r = 2 × π × 6
- ≈ 37.7 cm
2.A circle has a radius of 13 cm. What is its diameter?
Answer: 26 cm
The diameter is twice the radius.
3.A circle has a diameter of 4 cm. Find its circumference, correct to 1 decimal place.
Answer: 12.6 cm
- C = π × d = π × 4
- ≈ 12.6 cm
4.A circle has a radius of 7 cm. Find its area, correct to 1 decimal place.
Answer: 153.9 cm2
- A = π × r2 = π × 72 = π × 49
- ≈ 153.9 cm2
5.A circle has a diameter of 26 cm. Find its area, correct to 1 decimal place.
Answer: 530.9 cm2
- r = 26 ÷ 2 = 13 cm
- A = π × r2 = π × 132 = π × 169
- ≈ 530.9 cm2
6.A circle has a radius of 11 cm. Find its circumference, correct to 1 decimal place.
Answer: 69.1 cm
- C = 2 × π × r = 2 × π × 11
- ≈ 69.1 cm
7.A circle has a radius of 10 cm. Find its circumference, correct to 1 decimal place.
Answer: 62.8 cm
- C = 2 × π × r = 2 × π × 10
- ≈ 62.8 cm
8.A circle has a radius of 2 cm. Find its circumference, correct to 1 decimal place.
Answer: 12.6 cm
- C = 2 × π × r = 2 × π × 2
- ≈ 12.6 cm
9.A circle has a radius of 20 cm. What is its diameter?
Answer: 40 cm
The diameter is twice the radius.
10.A circle has a radius of 19 cm. Find its area, correct to 1 decimal place.
Answer: 1134.1 cm2
- A = π × r2 = π × 192 = π × 361
- ≈ 1134.1 cm2
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