Circumference of a circle: radius or diameter
Circumference = π × diameter, with π = 3.14. Double the radius to get the diameter.
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A circle has a diameter of 78 cm. Find its circumference. Use π = 3.14.
Answer: 244.92
A circle has a diameter of 98 cm. Find its circumference. Use π = 3.14.
Answer: 307.72
A circle has a radius of 53 cm. Find its circumference. Use π = 3.14.
Answer: 332.84
Tip: Circumference = π × diameter, with π = 3.14. Double the radius to get the diameter.
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