MathDB
Moldova Team Selection Test

Source: Moldova IMO TST 2002

November 18, 2017
combinatorics

Problem Statement

Let S={a1,,an}S= \{ a_1, \ldots, a_n\} be a set of n1n\geq 1 positive real numbers. For each nonempty subset of SS the sum of its elements is written down. Show that all written numbers can be divided into nn classes such that in each class the ratio of the greatest number to the smallest number is not greater than 22.