Success TutoringWorksheets

Year 7 Circumference and Area of Circles Worksheet — Level 3 — Answers

Answer sheet with worked solutions for the Year 7 area & perimeter worksheet.

Download answers PDFPrint answersBack to worksheet
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · Area & Perimeter

Year 7 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.A circle has a circumference of 38π cm. Find its radius and its area (leave the area in terms of π).

Answer: r = 19 cm; A = 361π cm2

  1. C = 2πr, so 2πr = 38π
  2. r = 19 cm
  3. A = πr2 = 361π cm2
2.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
3.Find the area of a semicircle with a radius of 5 cm, correct to 1 decimal place.

Answer: 39.3 cm2

  1. A = ½ × π × r2 = ½ × π × 25
  2. ≈ 39.3 cm2
4.A circle has a circumference of 6π cm. Find its radius and its area (leave the area in terms of π).

Answer: r = 3 cm; A = 9π cm2

  1. C = 2πr, so 2πr = 6π
  2. r = 3 cm
  3. A = πr2 = 9π cm2
5.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
6.A circle has a circumference of 18π cm. Find its radius and its area (leave the area in terms of π).

Answer: r = 9 cm; A = 81π cm2

  1. C = 2πr, so 2πr = 18π
  2. r = 9 cm
  3. A = πr2 = 81π cm2
7.Find the area of a semicircle with a radius of 15 cm, correct to 1 decimal place.

Answer: 353.4 cm2

  1. A = ½ × π × r2 = ½ × π × 225
  2. ≈ 353.4 cm2
8.A circle has a circumference of 4π cm. Find its radius and its area (leave the area in terms of π).

Answer: r = 2 cm; A = 4π cm2

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

Answer: 113.1 cm2

  1. A = π × r2 = π × 62 = π × 36
  2. ≈ 113.1 cm2
10.A circle has a radius of 13 cm. Find its area, correct to 1 decimal place.

Answer: 530.9 cm2

  1. A = π × r2 = π × 132 = π × 169
  2. ≈ 530.9 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: