CombinatoricsDifficulty 5.0AIME, harderFind the answerUnited Kingdom
There are n distinct lines in the plane. One of these lines intersects exactly 5 of the n lines, another of these intersects exactly 9 of the n lines, and yet another intersects exactly 11 of them. Which of the following is the smallest possible value of n?
(A) 12 (B) 13 (C) 14 (D) 25 (E) 28
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