9th Grade Circumference and Area of Circles Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 9th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Area & Perimeter9th 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.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
2.A circle has a diameter of 30 cm. Find its circumference, correct to 1 decimal place.
Answer: 94.2 cm
- C = π × d = π × 30
- ≈ 94.2 cm
3.A circle has a radius of 15 cm. Find its circumference, correct to 1 decimal place.
Answer: 94.2 cm
- C = 2 × π × r = 2 × π × 15
- ≈ 94.2 cm
4.Find the area of a semicircle with a radius of 3 cm, correct to 1 decimal place.
Answer: 14.1 cm2
- A = ½ × π × r2 = ½ × π × 9
- ≈ 14.1 cm2
5.A circle has a diameter of 20 cm. Find its circumference, correct to 1 decimal place.
Answer: 62.8 cm
- C = π × d = π × 20
- ≈ 62.8 cm
6.A circle has a radius of 8 cm. Find its area, correct to 1 decimal place.
Answer: 201.1 cm2
- A = π × r2 = π × 82 = π × 64
- ≈ 201.1 cm2
7.A circle has a radius of 14 cm. Find its area, correct to 1 decimal place.
Answer: 615.8 cm2
- A = π × r2 = π × 142 = π × 196
- ≈ 615.8 cm2
8.A circle has a diameter of 6 cm. Find its circumference, correct to 1 decimal place.
Answer: 18.8 cm
- C = π × d = π × 6
- ≈ 18.8 cm
9.A circle has a diameter of 14 cm. Find its circumference, correct to 1 decimal place.
Answer: 44.0 cm
- C = π × d = π × 14
- ≈ 44.0 cm
10.A circle has a radius of 3 cm. Find its circumference, correct to 1 decimal place.
Answer: 18.8 cm
- C = 2 × π × r = 2 × π × 3
- ≈ 18.8 cm
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