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Ball Packing
Age 14 to 16
Challenge Level 
| If a ball is rolled into the corner of a room how far is its
centre from the corner?
A sphere of diameter $10$cm is packed into a cubic box whose internal side lengths are $12$cm. To prevent the sphere from rolling around 8 identical smaller spheres are placed in the corners of the box. What is the radius of one of the smaller spheres? |
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