Everyone shakes hands with everyone else in a room. Total number of handshakes is 55. Number of persons=?
Choose the correct option
A) 14
B) 12
C) 11
D) 15
E) 16
In a room of n people, the number of possible handshakes is 11(n,2) or n(n-1)/2   So n(n-1)/2 = 55 OR n(n-1)=110 OR n=11   Answer is (11)
<result>C</result>
Everyone shakes hands with everyone else in a room. Total number of handshakes is 55. Number of persons=?