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Find the Circumference.​

Find the Circumference.​-example-1
User Princesa
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1 Answer

28 votes
28 votes

Answer:

1.

r = 12 m.

d = 24 m.

circumference: 75.36 m² or 24π m²

2.

r = 10 cm.

d = 20 cm.

circumference: 62.8 cm² or 20π cm²

3.

r = 4 dm.

d = 24 dm.

circumference: 25.12 dm² or 8π dm²

Explanation:

  • Circumference of a circle: 2πr
  • π (pi) = 3.14
  • r (radius) = d/2
  • d (diamater) = 2r

Substitute the the values of the table into the formula:

1.

r = 12 m.

d = 24 m.

circumference: 75.36 m² or 24π m²

2πr

2 * 3.14 * 12

3.14 * 24

75.36 m² or 24π m² <== circumference

12 * 2 = 24 m <== diameter

2.

r = 10 cm.

d = 20 cm.

circumference: 62.8 cm² or 20π cm²

r = 20/2 = 10 cm <== radius

2πr

2 * 3.14 * 10

3.14 * 20

62.8 cm² or 20π cm² <== circumference

3.

r = 4 dm.

d = 24 dm.

circumference: 25.12 dm² or 8π dm²

2πr

2 * 3.14 * 4

3.14 * 8

25.12 dm² or 8π dm² <== circumference

4 * 2 = 8 dm <== diameter

Hope this helps!

User Borko Kovacev
by
2.9k points