IF 36 GAMES WERE PLAYED AT A CHESS TOURNAMENT WITH EACH CONTESTENT PLAYING ONCE AGAINST EACH OTHER ;THEN THE NO OF PARTICIPENTS IS?

a) 6 b) 7 c) 8 d)9

i think it is 9

ans is 9

becoz 1st player cn play wid othr 8 and

nxt playr cn be grouped wid remainin 7 as a match wid  1st player is already arranged........so on .......... 

the ans is 8+7+6+......+2+1=36

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