Shouldn't the answer to the sample be 0.3660?
I've solved this problem assuming, that pyramid lies on triangular edge. It seems to me that it is wrong suggestion, nevertheless it got AC. It seems to me, that pyramid should be firstly rotated to lay on one of the triangular face - then the answer is 0.3660. Am I wrong?

Edited by author 09.11.2009 02:17