A group of 23 friends gets together to play a sport. First, people must be divided into teams. Each team has to have exactly 4 players, and no one can be on more than one team. How many teams can they

A group of 23 friends gets together to play a sport. First, people must be divided into teams. Each team has to have exactly 4 players, and no one can be on more than one team. How many teams can they make? (It is possible that not everyone can be on a team.)