Pick two points at random on a circle and draw the chord connecting them.

Pick two more points and connect them with a second chord.

What is the probability that these chords intersect?

Well, apparently this is major overkill, but continuing the logic from my earlier post:

The integral from 0 to 1 of 2x*(1-x)dx =

The integral from 0 to 1 of (2x - 2x^2)dx =

x^2 - 2/3(X^3) evaluated at 1 =

1 - 2/3  = 1/3

Just as Stephanie suggested!

Posted by Steve Herman on 2009-05-11 20:45:02