"A. Keyton Weissinger" <keyton at weissinger.org> schrieb > Good stuff in here, Karl. What are these examples from? Well, Kirby Urner is a math teacher (http://www.inetarena.com/~pdx4d/ocn), it seems, and the question of the original poster looked like some kind home work problem. Karl M. Syring <snip>