There are eight players in a tennis tournament.  The players must play games in pairs.  Each player must play one game with every other player.  How many games will be played in total?



Make a chart and look for a pattern.  First give each player a different letter.  Start with two players.  The number of games is the number of match-ups between players.  Each time you add a player, the new player must play a game with every other player already listed.  When you add player three you add two more games.  When you add player four you add three more games. Do this until you have added all eight players.

There will be 28 games played by 8 players.