a b and c are digits not integers, good idea though. If they were integers there would still be smaller answer then what you have found here. can you find that answer too?

If we know the average area of a randomly drawn triangle inside a unit circle, then the problem is solved. How do you find the average area of triangle? Where does 35/48Pi come from?
http://mathworld.wolfram.com/DiskTrianglePicking.html