Vidyarthiplus (V+) - Indian Students Online Education Forum

Karthik is in a business meeting
Every Businessmen handshake to all businessmen 

Karthik counts their  handshake
Totally 66 times handshake means, how many members in that meeting

one condition: no one handshake repeatly

Ans: 12!Am I rite?

I remember that using Permutations and Combination, i solved this in my 12th..