A square's area is equal to a circle's area. If the side of the square is 4 cm, what is the circumference of the circle?
Category: Math · Difficulty: hard
Hint: Calculate the area of the square first.
Answer
25.13 cm
Explanation
Area of the square = 4^2 = 16 cm², thus the circle's area is 16 cm². Radius r = √(16/π), circumference = 2πr ≈ 25.13 cm.
This is a hard math riddle — a tricky one that takes a little thought. The answer is 25.13 cm.
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