In a party every person shakes hands with every other person. If there were a total of 171 handshakes in the party then what is the number of persons present in the party ? Choose the correct choice from the following options
A) 15 B) 16 C) 17 D) 18 E) 19

Rationale: explanation : let the number of persons be n â ˆ ´ total handshakes = nc 2 = 171 n ( n - 1 ) / 2 = 171 â ˆ ´ n = 19 answer : option e
Answer: E