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Homework Help: Please help; combination problem

  1. Sep 23, 2010 #1
    1. The problem statement, all variables and given/known data

    there are N points on a paper. any three of points are not colinear.

    you draw lines from each point to all other points.lines can be drawn with three colors; red,yellow or blue.

    there will be obtained some triangles having colored edges.

    purpose is not to get a triangle, edges of which are drawn with the same color.

    what can be the value N at maximum?

    2. Relevant equations

    the number of triagles from N given points : N*(N-1)/2

    3. The attempt at a solution

    I can not get any mathematical expression for solution.
    I did try with considering all combinations for two color condition and I got N=5 maximum.
    for three color my trial was getting complicatd and I could not go on any more. But for N=10
    I am sure it is possible to get all triangles satisfying the condition.
  2. jcsd
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