Question

a set of football matches is to be organisedin a round robin fashion ie every participating team plays a match against every other team once and only once.If 28 matches are totally played how many teams participated.

Answer 1

Answer :

We know in round robin fashion " Every participating team plays a match against every other team once and only once. "

So,
2 teams would require 1 game

3 teams would require 2 + 1 = 3 games

4 teams require 3 + 2 + 1 = 6 games

5 teams require 4 + 3 + 2 + 1 = 10 games

6 teams require 5 + 4 + 3 + 2 + 1 = 15 games

7 teams require 6 + 5 + 4 + 3 + 2 + 1 = 21 games

So,

8 teams require 7 + 6 + 5 + 4 + 3 + 2 + 1 = 28 games
So,

Total number of teams participated = 8 ( Ans )