# Packing Nine Balls in a Cube

Geometry Level 3

9 identical, spherical balls are packed into a cube of edge length 100.

The 8 balls in corners are each tangent to the three faces making up its corner, and the $$9^\text{th}$$ ball is tangent to the other 8.

What is the radius of the spherical balls, to 1 decimal place?

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