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UKMT Grey Kangaroo, 2016

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Seven standard dice are glued together to make the solid shown. The pairs of faces of the dice that are glued together have the same number of dots on them. How many dots are on the surface of the solid?

(A) $24$ (B) $90$ (C) $95$ (D) $105$ (E) $126$

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