Question
At the conclusion of a party, a total number of 28
handshakes were exchanged. Every person in the party shook hands with every other person who atended the party. What was the total number of persons who atended the party?Solution
Let n be the number of people present. For every handshake, 2 persons are required. Since each handshake is between two persons, the total number of handshakes = nC2 =28 n! /{(n-2)! * 2!} = 28 n(n-1) = 56 So, n =8
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