You are provided with a circle, a triangle, and a square which each have the same length perimeter. If the circle is rotated, without slipping, around each of the other two, in which case will it rotate through the greatest number of degrees?

hi, first time on this site, first post, so excuse me if I am being totally stupid. here goes;

I agree with the rest of you people, but came up with my own explanation after thinking it through carefully. first of all, wether the circle rotates around a square or around any other type of rectangle seems insignificant to me. that's just my intuition though... so, let's say we make it rotate around a triangle and a rectangle, the next thing I do is specify their shapes. To make it easy for me to grasp, I create the most extreme cases possible: I stretch them out as much as I can. this will result in what seems like two lines with length = perimeter/2 . the only difference is on one end of those lines; the rectangle has two 'edges' and the triangle only one. though, because the space between those two edges of the rectangle is infinitely small, I take the liverty of saying that they are 'as good as identical'. with this in mind, the rest of the riddle seems self-explanatory enough to me...

I hope I am allowed to do what I just did; I like to think of things in an abstract way =]

thanks for the riddle,
-kabuto.

Posted by kabuto on 2005-07-17 19:16:17