Find the radius from the circumference
Radius from the circumference
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Find the radius of the circle. Use π ≈ 3.14.
The circumference of a circle is O = 18.84 cm. What is the radius?
cm
What does the generator do?
The generator picks an integer radius between 1 and 10 cm and shows the circumference as a multiple of 6.28 (for example 6.28, 12.56, 18.84). The expected answer is the radius — a small integer; the check accepts ±0.1.
How to solve
Divide the given circumference by 2 · π ≈ 6.28. The result is the radius. Because we picked nice numbers, it should come out as a whole number of centimetres.
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