Question 805578
 there are n teams in a league. if each team plays the others twice then how many matches are there in total? 
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Assume 3 teams:: a,b,c
Games: ab,ab,ac,ac,bc,bc------6 = 3^2-3
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Assume 4 teams:: a,b,c,d
ab twice
ac twice
ad twice
bc twice
bd twice
cd twice
Games:  12 = 4^2-4
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Assume n teams:::
Games:: n^2-n

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Cheers,
Stan H.
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