MathDB
Putnam 2005 A6

Source:

December 5, 2005
Putnamprobabilitycalculusfunctionintegrationgeometrygeometric transformation

Problem Statement

Let nn be given, n4,n\ge 4, and suppose that P1,P2,,PnP_1,P_2,\dots,P_n are nn randomly, independently and uniformly, chosen points on a circle. Consider the convex nn-gon whose vertices are the Pi.P_i. What is the probability that at least one of the vertex angles of this polygon is acute.?