Joey and his five brothers are ages , , , , , and . One afternoon two of his brothers whose ages sum to went to the movies, two brothers younger than went to play baseball, and Joey and the -year-old stayed home. How old is Joey?
Pick one
Solution
Because the -year-old stayed home, we know that the -year-old did not go to the movies, as the -year-old did not and . Also, the -year-old could not have gone to play baseball, as he is older than . Thus, the -year-old must have stayed home, so Joey is
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