I have no corners, no straight sides, and no end, yet every point on me is the exact same distance from my center. Multiply my radius by two and pi, and you will find my outer boundary. What shape am I?
Circle
A circle is defined as all points equidistant from a center point, and its circumference (outer boundary) is calculated using the formula 2 * pi * r.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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