Two members of a club are to be selected to represent the club at a national meeting. if there are 91 different possible selections of the 2 members, how many members does the club have? Options:  A) 20  B) 14  C) 40  D) 57  E) 95
I have done this problem by substituting numbers   We have n!/2!(n-2)! = 91   or n(n-1)/2 = 182 or (n-14)(n+13) =0   n=14 satisfies the equation   14
<result>B</result>
Two members of a club are to be selected to represent the club at a national meeting. if there are 91 different possible selections of the 2 members, how many members does the club have?