7th Grade Circumference and Area of Circles Worksheet — Level 1 — Practice Set 2 — 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 1 — Practice Set 2 — 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 16 cm. What is its diameter?
Answer: 32 cm
The diameter is twice the radius.
2.A circle has a diameter of 30 cm. What is its radius?
Answer: 15 cm
The radius is half the diameter.
3.A circle has a radius of 10 cm. What is its diameter?
Answer: 20 cm
The diameter is twice the radius.
4.A circle has a radius of 11 cm. Find its circumference, correct to 1 decimal place.
Answer: 69.1 cm
- C = 2 × π × r = 2 × π × 11
- ≈ 69.1 cm
5.A circle has a radius of 17 cm. Find its circumference, correct to 1 decimal place.
Answer: 106.8 cm
- C = 2 × π × r = 2 × π × 17
- ≈ 106.8 cm
6.A circle has a radius of 13 cm. Find its circumference, correct to 1 decimal place.
Answer: 81.7 cm
- C = 2 × π × r = 2 × π × 13
- ≈ 81.7 cm
7.A circle has a diameter of 8 cm. Find its area, correct to 1 decimal place.
Answer: 50.3 cm2
- r = 8 ÷ 2 = 4 cm
- A = π × r2 = π × 42 = π × 16
- ≈ 50.3 cm2
8.A circle has a radius of 5 cm. Find its circumference, correct to 1 decimal place.
Answer: 31.4 cm
- C = 2 × π × r = 2 × π × 5
- ≈ 31.4 cm
9.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
10.A circle has a radius of 11 cm. What is its diameter?
Answer: 22 cm
The diameter is twice the radius.
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