Year 10 Circumference and Area of Circles Worksheet — Level 1 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 10 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 10 · Mathematics · Area & PerimeterYear 10 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 diameter of 12 cm. What is its radius?
Answer: 6 cm
The radius is half the diameter.
2.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
3.A circle has a diameter of 36 cm. What is its radius?
Answer: 18 cm
The radius is half the diameter.
4.A circle has a diameter of 38 cm. What is its radius?
Answer: 19 cm
The radius is half the diameter.
5.A circle has a radius of 8 cm. Find its circumference, correct to 1 decimal place.
Answer: 50.3 cm
- C = 2 × π × r = 2 × π × 8
- ≈ 50.3 cm
6.A circle has a radius of 3 cm. What is its diameter?
Answer: 6 cm
The diameter is twice the radius.
7.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
8.A circle has a diameter of 30 cm. What is its radius?
Answer: 15 cm
The radius is half the diameter.
9.A circle has a radius of 8 cm. What is its diameter?
Answer: 16 cm
The diameter is twice the radius.
10.A circle has a diameter of 20 cm. What is its radius?
Answer: 10 cm
The radius is half the diameter.
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