MathDB
Putnam 1985 B4

Source:

August 5, 2019
Putnamprobability

Problem Statement

Let CC be the unit circle x2+y2=1.x^{2}+y^{2}=1 . A point pp is chosen randomly on the circumference CC and another point qq is chosen randomly from the interior of CC (these points are chosen independently and uniformly over their domains). Let RR be the rectangle with sides parallel to the xx and yy-axes with diagonal pq.p q . What is the probability that no point of RR lies outside of C?C ?