1. The problem statement, all variables and given/known data this isnt a homeowrk question as such - its a question that my Grandpa asked me. You have a circular field, and a goat tied up to a post which is somewhere on the cirumference of the field. How long does is the rope if the goat is able to eat exactly half of the grass in the field 2. Relevant equations area of field = pi * r^2, and say for arguments sake that the radius of the field is 10 meters. let r be radius of field and R be radius goats rope 3. The attempt at a solution I thought that you would maximise by differentiating at first, or solving a quadratic but unsuprisingly its not that simple!