Year 8 Circumference and Area of Circles Worksheet — Level 1 — 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 — 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 5 cm. What is its diameter?
Answer: 10 cm
The diameter is twice the radius.
2.A circle has a diameter of 26 cm. What is its radius?
Answer: 13 cm
The radius is half the diameter.
3.A circle has a diameter of 22 cm. What is its radius?
Answer: 11 cm
The radius is half the diameter.
4.A circle has a radius of 14 cm. What is its diameter?
Answer: 28 cm
The diameter is twice the radius.
5.A circle has a diameter of 14 cm. Find its circumference, correct to 1 decimal place.
Answer: 44.0 cm
- C = π × d = π × 14
- ≈ 44.0 cm
6.A circle has a diameter of 10 cm. Find its circumference, correct to 1 decimal place.
Answer: 31.4 cm
- C = π × d = π × 10
- ≈ 31.4 cm
7.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
8.A circle has a diameter of 20 cm. Find its circumference, correct to 1 decimal place.
Answer: 62.8 cm
- C = π × d = π × 20
- ≈ 62.8 cm
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.A circle has a diameter of 32 cm. Find its area, correct to 1 decimal place.
Answer: 804.2 cm2
- r = 32 ÷ 2 = 16 cm
- A = π × r2 = π × 162 = π × 256
- ≈ 804.2 cm2
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