Thread: How to calculate the number of combinations of matches in each group of a tournament?

A tournament has 6 groups.

Each group has 4 players.

Every player will play with every player of the same group once and the top two players will qualify for the next level.

I know that each group will have 6 matches. But how to calculate that mathematically? What if there are 5, 6, 7 or 8 players in each group?

You have to use Combination here.
The number of possible matches between 4 players is (one player vs another)
4C2=4!/2!*2!
=6 matches.

If there are 5 players,no.of matches is
5C2=5!/3!*2!
=10 matches.

For 6 players, there are 15 matches.
For 7 players, there are 21 matches.
For 8 players, there are 28 matches.

Each group will have n(n-1)/2 matches, where 'n' stands for number of players in that respective group.