Arthur D. answered 11/20/17
Tutor
4.9
(274)
Forty Year Educator: Classroom, Summer School, Substitute, Tutor
suppose the teams are...
A, B, C, D, E, F, G, H
and they play each other only once...
A plays B,C,D,E,F,G,H for a total of 7 games
B plays C,D,E,F,G,H for a total of 6 games (A already played B)
C plays D,E,F,G,H for a total of 5 games (C already played A and B)
D plays 4 games
E plays 3 games
F plays 2 games
G plays 1 game
H (everybody played H)
7+6+5+4+3+2+1=28 games played if each team plays every other team just once
but they play each other twice so 2*28=56 games played altogether
there is a pattern
if there are 3 teams A,B,C
A plays B twice, A plays C twice, and B plays C twice for a total of 6 games
3 teams times 2=6 games
4 teams A,B,C,D
A plays B twice, A plays C twice, A plays D twice, B plays C twice, B plays D twice, C plays D twice for a total of 12 games
4 teams times 3=12 games
5 teams, 5*4=20 games
6 teams, 6*5=30 games
7 teams, 7*6=42 games
8 teams, 8*7=56 games where each team plays every other team twice

Arthur D.
11/20/17