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Last Updated on May 5, 2023
GMAT OFFICIAL GUIDE PS
Solution:
We are given that there are 8 teams in a league and that each game is played by 2 teams. Note that each team does not play itself, and the order of pairing each team with its opponent doesn’t matter. [For example, the pairing of (Team A vs. Team B) is identical to the pairing of (Team B vs. Team A).] The situation can therefore be solved by finding the number of combinations of 8 items taken 2 at a time, or 8C2, as follows:
8C2 = 8! / [2! x (8-2)!]
8! / (2! x 6!)
(8 x 7)/2!
8 x 7 / 2
4 x 7 = 28
Answer: C
