Question
Salman has a list of 12 friends. He wishes to invite
some of them in such a manner that he can enjoy maximum number of parties, but in each party the numberof  friends (i.e., invitees) be same and each party must have different set of person. Then how many parties can Salman?Solution
If n is even, nCr is maximum when r = n/2 Â Number of invitees in a party = 12/2 = 6 and Maximum possible number of parties = 12C6 = 924Â Â Â Â Â Â Â
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