Year 8 Circumference and Area of Circles Worksheet — Level 1 — Practice Set 4 — 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 4 — 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 17 cm. Find its area, correct to 1 decimal place.
Answer: 907.9 cm2
- A = π × r2 = π × 172 = π × 289
- ≈ 907.9 cm2
2.A circle has a diameter of 36 cm. Find its circumference, correct to 1 decimal place.
Answer: 113.1 cm
- C = π × d = π × 36
- ≈ 113.1 cm
3.A circle has a diameter of 6 cm. What is its radius?
Answer: 3 cm
The radius is half the diameter.
4.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
5.A circle has a radius of 9 cm. Find its circumference, correct to 1 decimal place.
Answer: 56.5 cm
- C = 2 × π × r = 2 × π × 9
- ≈ 56.5 cm
6.A circle has a diameter of 18 cm. What is its radius?
Answer: 9 cm
The radius is half the diameter.
7.A circle has a radius of 8 cm. Find its area, correct to 1 decimal place.
Answer: 201.1 cm2
- A = π × r2 = π × 82 = π × 64
- ≈ 201.1 cm2
8.A circle has a radius of 14 cm. What is its diameter?
Answer: 28 cm
The diameter is twice the radius.
9.A circle has a diameter of 24 cm. What is its radius?
Answer: 12 cm
The radius is half the diameter.
10.A circle has a radius of 9 cm. What is its diameter?
Answer: 18 cm
The diameter is twice the radius.
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