Year 7 Circumference and Area of Circles Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 7 area & perimeter worksheet.
Year 7 Circumference and Area of Circles Worksheet — Level 2 — Practice Set 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 diameter of 8 cm. Find its circumference, correct to 1 decimal place.
Answer: 25.1 cm
- C = π × d = π × 8
- ≈ 25.1 cm
2.Find the area of a semicircle with a radius of 17 cm, correct to 1 decimal place.
Answer: 454.0 cm2
- A = ½ × π × r2 = ½ × π × 289
- ≈ 454.0 cm2
3.A circle has a radius of 14 cm. Find its circumference, correct to 1 decimal place.
Answer: 88.0 cm
- C = 2 × π × r = 2 × π × 14
- ≈ 88.0 cm
4.A circle has a diameter of 18 cm. Find its circumference, correct to 1 decimal place.
Answer: 56.5 cm
- C = π × d = π × 18
- ≈ 56.5 cm
5.Find the area of a semicircle with a radius of 4 cm, correct to 1 decimal place.
Answer: 25.1 cm2
- A = ½ × π × r2 = ½ × π × 16
- ≈ 25.1 cm2
6.A circle has a diameter of 32 cm. Find its circumference, correct to 1 decimal place.
Answer: 100.5 cm
- C = π × d = π × 32
- ≈ 100.5 cm
7.Find the area of a semicircle with a radius of 10 cm, correct to 1 decimal place.
Answer: 157.1 cm2
- A = ½ × π × r2 = ½ × π × 100
- ≈ 157.1 cm2
8.A circle has a radius of 17 cm. Find its area, correct to 1 decimal place.
Answer: 907.9 cm2
- A = π × r2 = π × 172 = π × 289
- ≈ 907.9 cm2
9.A circle has a diameter of 12 cm. Find its area, correct to 1 decimal place.
Answer: 113.1 cm2
- r = 12 ÷ 2 = 6 cm
- A = π × r2 = π × 62 = π × 36
- ≈ 113.1 cm2
10.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
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.