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Circumference of a Circle

• Radius: A segment with one endpoint at the center and one on the circle
• Diameter: A segment that passes through the center and whose endpoints are on the circle
• Chord: A segment whose endpoints are on the circle
• Circumference: The distance around the circle
• Circumference = 2πr

Find the circumference of each circle with the given measure. radius = 12 in

• C = 2πr
• C = 2(3.14)(12)
• C = 24(3.14)

Find the circumference of each circle with the given measure. radius = 5 cm

• C = 2πr
• C = 2(3.14)(5)
• C = 10(3.14)

Find the circumference of each circle with the given measure. radius = 3 in

• C = 2πr
• C = 2(3.14)(3)
• C = 6(3.14)

• C = 2πr
• C = dπ
• C = 8(3.14)

Find the circumference of each circle with the given measure. diameter = 13 cm

• C = 2πr
• C = dπ
• C = 13(3.14)

C = 40.82 cm

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.