math
posted by Mathslover on .
Let S be a set of 31 equally spaced points on a circle centered at O, and consider a uniformly random pair of distinct points A and B (A,B∈S). The probability that the perpendicular bisectors of OA and OB intersect strictly inside the circle can be expressed as mn, where m,n are relatively prime positive integers. Find m+n

I think you mean probability is m/n, where m≤n.

yes

is it 5