If the radius of a circle is doubled, how does its circumference change?
Category: Math · Difficulty: hard
Hint: Recall the formula for circumference.
Answer
It becomes twice as long.
Explanation
Circumference = 2πr, so doubling r results in doubling the circumference.
This is a hard math riddle — a tricky one that takes a little thought. The answer is It becomes twice as long..
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