Circumference of a circle from the radius
Circumference from the radius
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Compute the circumference of the circle. Use π ≈ 3.14 and round to 1 decimal.
The radius of the circle is r = 5 cm. What is the circumference?
cm
What does the generator do?
The generator picks an integer radius between 2 and 20 cm and asks for the circumference. The expected answer is rounded to 1 decimal place; the check accepts any value within ±0.1 to absorb rounding choices.
How to solve
Multiply the radius by 2, then by π ≈ 3.14. Write the result with one decimal place. Always include the unit (cm).
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