Success TutoringWorksheets

9th Grade Circumference and Area of Circles Worksheet — Level 1 — Practice Set 3 — Answers

Answer sheet with worked solutions for the 9th Grade area & perimeter worksheet.

Download answers PDFPrint answersBack to worksheet
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Area & Perimeter

9th Grade Circumference and Area of Circles Worksheet — Level 1 — Practice Set 3 — Answers

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

1.A circle has a radius of 3 cm. Find its area, correct to 1 decimal place.

Answer: 28.3 cm2

  1. A = π × r2 = π × 32 = π × 9
  2. ≈ 28.3 cm2
2.A circle has a radius of 17 cm. Find its circumference, correct to 1 decimal place.

Answer: 106.8 cm

  1. C = 2 × π × r = 2 × π × 17
  2. ≈ 106.8 cm
3.A circle has a radius of 14 cm. Find its area, correct to 1 decimal place.

Answer: 615.8 cm2

  1. A = π × r2 = π × 142 = π × 196
  2. ≈ 615.8 cm2
4.A circle has a radius of 18 cm. Find its area, correct to 1 decimal place.

Answer: 1017.9 cm2

  1. A = π × r2 = π × 182 = π × 324
  2. ≈ 1017.9 cm2
5.A circle has a radius of 15 cm. What is its diameter?

Answer: 30 cm

The diameter is twice the radius.

6.A circle has a radius of 7 cm. What is its diameter?

Answer: 14 cm

The diameter is twice the radius.

7.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
8.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
9.A circle has a diameter of 14 cm. Find its circumference, correct to 1 decimal place.

Answer: 44.0 cm

  1. C = π × d = π × 14
  2. ≈ 44.0 cm
10.A circle has a diameter of 12 cm. Find its circumference, correct to 1 decimal place.

Answer: 37.7 cm

  1. C = π × d = π × 12
  2. ≈ 37.7 cm
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: