8th Grade Circumference and Area of Circles Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 8th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Area & Perimeter8th 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 6 cm, correct to 1 decimal place.
Answer: 56.5 cm2
- A = ½ × π × r2 = ½ × π × 36
- ≈ 56.5 cm2
2.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
3.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
4.A circle has a radius of 13 cm. Find its area, correct to 1 decimal place.
Answer: 530.9 cm2
- A = π × r2 = π × 132 = π × 169
- ≈ 530.9 cm2
5.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
6.Find the area of a semicircle with a radius of 11 cm, correct to 1 decimal place.
Answer: 190.1 cm2
- A = ½ × π × r2 = ½ × π × 121
- ≈ 190.1 cm2
7.Find the area of a semicircle with a radius of 9 cm, correct to 1 decimal place.
Answer: 127.2 cm2
- A = ½ × π × r2 = ½ × π × 81
- ≈ 127.2 cm2
8.A circle has a radius of 5 cm. Find its area, correct to 1 decimal place.
Answer: 78.5 cm2
- A = π × r2 = π × 52 = π × 25
- ≈ 78.5 cm2
9.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
10.A circle has a diameter of 20 cm. Find its area, correct to 1 decimal place.
Answer: 314.2 cm2
- r = 20 ÷ 2 = 10 cm
- A = π × r2 = π × 102 = π × 100
- ≈ 314.2 cm2
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