Success TutoringWorksheets

Year 10 Circumference and Area of Circles Worksheet — Level 3 — Answers

Answer sheet with worked solutions for the Year 10 area & perimeter worksheet.

Download answers PDFPrint answersBack to worksheet
Success TutoringWorksheetsAnswer sheetYear 10 · Mathematics · Area & Perimeter

Year 10 Circumference and Area of Circles Worksheet — Level 3 — Answers

Show your working. Use the π button on your calculator and round to 1 decimal place unless told otherwise.

1.Find the area of a semicircle with a radius of 20 cm, correct to 1 decimal place.

Answer: 628.3 cm2

  1. A = ½ × π × r2 = ½ × π × 400
  2. ≈ 628.3 cm2
2.A circle has a diameter of 14 cm. Find its area, correct to 1 decimal place.

Answer: 153.9 cm2

  1. r = 14 ÷ 2 = 7 cm
  2. A = π × r2 = π × 72 = π × 49
  3. ≈ 153.9 cm2
3.A circle has a circumference of 12π cm. Find its radius and its area (leave the area in terms of π).

Answer: r = 6 cm; A = 36π cm2

  1. C = 2πr, so 2πr = 12π
  2. r = 6 cm
  3. A = πr2 = 36π cm2
4.A circle has a radius of 8 cm. Find its area, correct to 1 decimal place.

Answer: 201.1 cm2

  1. A = π × r2 = π × 82 = π × 64
  2. ≈ 201.1 cm2
5.A circle has a diameter of 10 cm. Find its area, correct to 1 decimal place.

Answer: 78.5 cm2

  1. r = 10 ÷ 2 = 5 cm
  2. A = π × r2 = π × 52 = π × 25
  3. ≈ 78.5 cm2
6.Find the area of a semicircle with a radius of 17 cm, correct to 1 decimal place.

Answer: 454.0 cm2

  1. A = ½ × π × r2 = ½ × π × 289
  2. ≈ 454.0 cm2
7.A circle has a radius of 9 cm. Find its area, correct to 1 decimal place.

Answer: 254.5 cm2

  1. A = π × r2 = π × 92 = π × 81
  2. ≈ 254.5 cm2
8.A circle has a radius of 15 cm. Find its area, correct to 1 decimal place.

Answer: 706.9 cm2

  1. A = π × r2 = π × 152 = π × 225
  2. ≈ 706.9 cm2
9.Find the area of a semicircle with a radius of 11 cm, correct to 1 decimal place.

Answer: 190.1 cm2

  1. A = ½ × π × r2 = ½ × π × 121
  2. ≈ 190.1 cm2
10.A circle has a diameter of 16 cm. Find its area, correct to 1 decimal place.

Answer: 201.1 cm2

  1. r = 16 ÷ 2 = 8 cm
  2. A = π × r2 = π × 82 = π × 64
  3. ≈ 201.1 cm2
Free worksheets at worksheets.successtutoring.com · © Success Tutoring · Free for personal and classroom use

Marking tips

  • Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
  • For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
  • Celebrate what went well first, then pick one thing to work on next.

Great work. Here's what to try next: