CombinatoricsDifficulty 2.0JuniorFind the answerUnited Kingdom
You can choose four positive integers X, Y, Z and W. What is the maximum number of odd numbers you can obtain from the six sums X+Y, X+Z, X+W, Y+Z, Y+W and Z+W?
(A) 2 (B) 3 (C) 4 (D) 5 (E) 6
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