If the circumference of a circle is 31.4 cm, what is the area of the circle?
Category: Math · Difficulty: expert
Hint: Use the formulas for circumference and area of a circle.
Answer
77
Explanation
Circumference C = 2πr, solving gives radius r; area is πr^2.
This is a expert math riddle — one of the harder riddles here. The answer is 77.
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