Suppose that 20 red dots and 20 green dots are
randomly put on a piece of paper.
Is it always possible to draw straight line segments so that each red dot is
joined to one green dot, and so that none of the line segments intersect?
If so, why? If not, why not?
Assume that the dots are geometric points, so that they have
no size, only position.
Send your solution to sedwards@spsu.edu,
or by mail to Steve Edwards in the Math
Department. The names of the first solvers will be posted here.