Year 8 Circumference and Area of Circles Worksheet — Level 1 — Practice Set 2 — 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 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 32 cm. Find its circumference, correct to 1 decimal place.
Answer: 100.5 cm
- C = π × d = π × 32
- ≈ 100.5 cm
2.A circle has a diameter of 26 cm. Find its circumference, correct to 1 decimal place.
Answer: 81.7 cm
- C = π × d = π × 26
- ≈ 81.7 cm
3.A circle has a radius of 5 cm. What is its diameter?
Answer: 10 cm
The diameter is twice the radius.
4.A circle has a diameter of 24 cm. What is its radius?
Answer: 12 cm
The radius is half the diameter.
5.A circle has a radius of 9 cm. Find its area, correct to 1 decimal place.
Answer: 254.5 cm2
- A = π × r2 = π × 92 = π × 81
- ≈ 254.5 cm2
6.A circle has a radius of 13 cm. What is its diameter?
Answer: 26 cm
The diameter is twice the radius.
7.A circle has a diameter of 20 cm. Find its area, correct to 1 decimal place.
Answer: 314.2 cm2
- r = 20 ÷ 2 = 10 cm
- A = π × r2 = π × 102 = π × 100
- ≈ 314.2 cm2
8.A circle has a diameter of 26 cm. What is its radius?
Answer: 13 cm
The radius is half the diameter.
9.A circle has a radius of 15 cm. What is its diameter?
Answer: 30 cm
The diameter is twice the radius.
10.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
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