Reply #59: In #3, consider the point where the rope is attached

[bleever]

as the center of another circle, because from that point the cow can reach 100 feet straight out, to the left, and to the right. It's a half circle, easily calculated.

Wrapping around, how far does to cow reach from the point of the first circle? Basic geometry gives me (and my glass of bourbon)a distance of something like 76.5 feet. So the back half of the cow's range is half an oval, with a radius of 100 feet on the sides shrinking to 76.5 at the apex.

So, it's 100 squared times pi, minus 25 squared time pi, minus the crescent on the back side between 76.5 feet from the point of attachment and 100 feet out.

What that is exactly, I can't do the calculus for right now.

It's an open bar at Mensa functions, isn't it?