I am a civil engineering designer trying to design an egg shaped island. I want a 30' radius at the top and a 40' radius at the bottom and the longest length of the egg to be 125'. Is there standard geometry for an egg shape? I am not held to exact radii or the length given.

Thanks. Karen

Hi Karen,

Perhaps there is a standard way to produce general egg shapes; here is a way that is easy for somebody using a template with ellipses. Since the axes of an ellipse are perpendicular, it is easy to use one ellipse with a minor axis of length d on the left, and a second ellipse (or circle) whose axis is the same length d on the right. The egg below is half an ellipse on the left and a circle on the right. The result looks pretty good to me. In fact, you can join two ellipses at any point where their tangent lines match.

Cheers,
Chris
Go to Math Central