Area of a circle from the radius
Area from the radius
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Total answers
Compute the area of the circle. Use π ≈ 3.14 and round to 1 decimal.
The radius of the circle is r = 5 cm. What is the area?
cm²
What does the generator do?
The generator picks an integer radius between 2 and 10 cm and asks for the area. The expected answer is rounded to 1 decimal place; the check accepts any value within ±0.1.
How to solve
Square the radius first (r · r), then multiply by π ≈ 3.14. The unit of area is cm² — always include it.
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