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2013 AMC 10A Problem 25

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2013 AMC 10A Problem 25AMC 10 Step by Step
Name:                             Date: September 13, 2026
Basic Counting · difficulty 5 of 5 · about 10 min · position P21-25

All 20 diagonals are drawn in a regular octagon. At how many distinct points in the interior of the octagon (not on the boundary) do two or more diagonals intersect?

  1. A)

    4949

  2. B)

    6565

  3. C)

    7070

  4. D)

    9696

  5. E)

    128128

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