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Q. In a tournament, 28 games were played when each team plays one game. Then how many teams participated in this tournament?

(A) 7

(B) 8

(C) 9

(D) 10

(E) 11

n(n-1) / 2 = 28

n(n-1) = 56 = 8 x 7

**There fore n = 8**