7th Grade Circumference and Area of Circles Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 7th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Area & Perimeter7th Grade Circumference and Area of Circles Worksheet — Level 2 — 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 6 cm. Find its circumference, correct to 1 decimal place.
Answer: 37.7 cm
- C = 2 × π × r = 2 × π × 6
- ≈ 37.7 cm
2.Find the area of a semicircle with a radius of 8 cm, correct to 1 decimal place.
Answer: 100.5 cm2
- A = ½ × π × r2 = ½ × π × 64
- ≈ 100.5 cm2
3.A circle has a diameter of 22 cm. Find its circumference, correct to 1 decimal place.
Answer: 69.1 cm
- C = π × d = π × 22
- ≈ 69.1 cm
4.A circle has a radius of 4 cm. Find its circumference, correct to 1 decimal place.
Answer: 25.1 cm
- C = 2 × π × r = 2 × π × 4
- ≈ 25.1 cm
5.Find the area of a semicircle with a radius of 18 cm, correct to 1 decimal place.
Answer: 508.9 cm2
- A = ½ × π × r2 = ½ × π × 324
- ≈ 508.9 cm2
6.Find the area of a semicircle with a radius of 12 cm, correct to 1 decimal place.
Answer: 226.2 cm2
- A = ½ × π × r2 = ½ × π × 144
- ≈ 226.2 cm2
7.Find the area of a semicircle with a radius of 14 cm, correct to 1 decimal place.
Answer: 307.9 cm2
- A = ½ × π × r2 = ½ × π × 196
- ≈ 307.9 cm2
8.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
9.A circle has a diameter of 4 cm. Find its area, correct to 1 decimal place.
Answer: 12.6 cm2
- r = 4 ÷ 2 = 2 cm
- A = π × r2 = π × 22 = π × 4
- ≈ 12.6 cm2
10.Find the area of a semicircle with a radius of 2 cm, correct to 1 decimal place.
Answer: 6.3 cm2
- A = ½ × π × r2 = ½ × π × 4
- ≈ 6.3 cm2
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.