Two members of a club are to be selected to represent the club at a national meeting. if there are 120 different possible selections of the 2 members, how many members does the club have?	Choose the correct choice from the following answers.
A) 20  B) 27  C) 16  D) 57  E) 95
I have done this problem by substituting numbers   We have n!/2!(n-2)! = 120   or n(n-1)/2 = 120 or n^2-n =240 or (n-16)(n+15)   n=16 satisfies the equation   16
<result>C</result>
Two members of a club are to be selected to represent the club at a national meeting. if there are 120 different possible selections of the 2 members, how many members does the club have?