In a birthday party, every person shakes hand with every other person. If there was a total of 28 handshakes in the party, how many persons were present in the party?  Pick
A) 6	B) 7	C) 8	D) 9	E) 10
Suppose there are nn persons present in a party and every person shakes hand with every other person. Then, total number of handshakes   = n82=n(n−1)/2   n(n−1)=28×2n(n−1)=56   n=8   ANSWER 8 8
<result>C</result>
In a birthday party, every person shakes hand with every other person. If there was a total of 28 handshakes in the party, how many persons were present in the party?