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CEMC Gauss (Grade 7), 2010

Combinatorics Difficulty 1.0 Junior Find the answer Canada

Distinct points are placed on a circle. Each pair of points is joined with a line segment. An example with 4 points and 6 line segments is shown. If 6 distinct points are placed on a circle, how many line segments would there be?

(A) $13$ (B) $16$ (C) $30$ (D) $15$ (E) $14$

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