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2013 AMC 10A Question 25

AMC10 · 2013 AMC 10A

Question 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. $49$
  2. $65$
  3. $70$
  4. $96$
  5. $128$