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UKMT Pink Kangaroo, 2017

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

On a balance scale, three different masses were put at random on each pan and the result is shown in the picture. The masses are of 101, 102, 103, 104, 105 and 106 grams. What is the probability that the 106 gram mass stands on the heavier pan?

(A) $75\%$ (B) $80\%$ (C) $90\%$ (D) $95\%$ (E) $100\%$

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