Question 52
There are 924 fans of the Liechtenstein football team from either Liechtenstein or Switzerland who have gathered to get the autographs of their favourite players. There are 11 players on the team, and every fan has exactly 6 favourite players. No two people from a given country share the same group of favourites, and in the end everyone got exactly one autograph from one of their favourite players. Show that there is a player who gave an autograph to both a Swiss and a Liechtensteiner person.