Number theoryDifficulty 5.0Find the answerBMO Round 1 · United Kingdom · 2011
Let s be an integer greater than 6. A solid cube of side s has a square hole of side x<6 drilled directly through from one face to the opposite face (so the drill removes a cuboid). The volume of the remaining solid is numerically equal to the total surface area of the remaining solid. Determine all possible integer values of x.
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