A sphere is inscribed in a cube. What is the ratio of the radius of the inscribed sphere to the edge of the cube?

If you draw it, the diameter of the sphere is equal to the edge of the cube.

Good observation, dmgp. I hadn't thought of visualing it that way.

Since the question asked for the ratio of the radius to the edge,

the ratio would be 1 to 2 because the radius is half the diameter.

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