Another puzzle to mark the 2019 Rugby World Cup.
If 2019 teams enter a knockout competition, how many matches are needed to produce a winner. Assume that each match is played to a finish, with extra time, sudden death extra time and then a kicking competition to decide the winner - as is the case in the Rugby World Cup knockout matches.
As each match eliminates one team and we need one winner, we need to eliminate 2018 of the 2019 team, meaning 2018 matches.