IMO 2020 Problem 3
Working
Proposed by: -
Verified: no
Verdicts: UNKNOWN + UNKNOWN
Solve time: 43s
Problem
There are $4n$ pebbles of weights $1, 2, 3, . . . , 4n$. Each pebble is colored in one of $n$ colors and there are four pebbles of each color. Show that we can arrange the pebbles into two piles so that the following two conditions are both satisfied:
- The total weights of both piles are the same.
- Each pile contains two pebbles of each color.
Working