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 38 cm. Find its area, correct to 1 decimal place.
Answer: 1134.1 cm2
- r = 38 ÷ 2 = 19 cm
- A = π × r2 = π × 192 = π × 361
- ≈ 1134.1 cm2
2.A circle has a diameter of 8 cm. Find its area, correct to 1 decimal place.
Answer: 50.3 cm2
- r = 8 ÷ 2 = 4 cm
- A = π × r2 = π × 42 = π × 16
- ≈ 50.3 cm2
3.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
4.A circle has a radius of 10 cm. Find its area, correct to 1 decimal place.
Answer: 314.2 cm2
- A = π × r2 = π × 102 = π × 100
- ≈ 314.2 cm2
5.A circle has a diameter of 16 cm. What is its radius?
Answer: 8 cm
The radius is half the diameter.
6.A circle has a radius of 14 cm. What is its diameter?
Answer: 28 cm
The diameter is twice the radius.
7.A circle has a diameter of 14 cm. Find its area, correct to 1 decimal place.
Answer: 153.9 cm2
- r = 14 ÷ 2 = 7 cm
- A = π × r2 = π × 72 = π × 49
- ≈ 153.9 cm2
8.A circle has a radius of 13 cm. Find its area, correct to 1 decimal place.
Answer: 530.9 cm2
- A = π × r2 = π × 132 = π × 169
- ≈ 530.9 cm2
9.A circle has a radius of 12 cm. Find its area, correct to 1 decimal place.
Answer: 452.4 cm2
- A = π × r2 = π × 122 = π × 144
- ≈ 452.4 cm2
10.A circle has a diameter of 10 cm. Find its area, correct to 1 decimal place.
Answer: 78.5 cm2
- r = 10 ÷ 2 = 5 cm
- A = π × r2 = π × 52 = π × 25
- ≈ 78.5 cm2
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