Maths Olympiad Prep

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CEMC Pascal, 2005

Combinatorics Difficulty 2.0 Junior Find the answer Canada

Eight unit cubes are used to form a larger 2 by 2 by 2 cube. The six faces of this larger cube are then painted red. When the paint is dry, the larger cube is taken apart. What fraction of the total surface area of the unit cubes is red?

(A) 16\dfrac{1}{6} (B) 23\dfrac{2}{3} (C) 12\dfrac{1}{2} (D) 14\dfrac{1}{4} (E) 13\dfrac{1}{3}

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