Simplify the following: 2 / 5 to 3 / 4, 5 / 6 to 1 / 6

Simplify the following: 2 / 5 to 3 / 4, 5 / 6 to 1 / 6


8:15 5:1



3. The general formula of 6, 10, 15. N


General formula: an = (n + 1) (n + 2) / 2



Can we write a formula for the number of matches n of M teams in a single round robin competition with 3 teams, 3 games, 4 teams, 6 games, 5 teams and 10 games?


M stands for the number of teams, n stands for the number of games
N=(M-1)*(M÷2)