Find all values of N
Source: All Russian Grade 9 Day 2 P4
December 12, 2015
combinatorics
Problem Statement
distinct real numbers are written on a blackboard. All these numbers are nonnegative, and all are less than . It happens that for very distinct numbers on the board, the board contains the ninth number distinct from eight such that the sum of all these nine numbers is integer. Find all values for which this is possible. (F. Nilov)