Which fits you best?
Observe this diagram:
Considering that the radius of the circle is r, then the area of the circle is given by πr2 and the area of the outer square will be (2r)2 = 4r2.
We also realize that the blue square is exactly half the area of the outer square, so its area will be 2r2. We have then:
(Circle Area) / (Outer Square Area) = πr2 / 4r2 = π / 4, which is worth approximately 78.5%.
(Small square area) / (Circle area) = 2r2 / πr2 = 2 / π, which is worth approximately 63.7%.
Therefore, in the first case the piece fits better, as it occupies a larger area (78.5%).
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