Question

in how many ways could members of the following club line up all 7 members for a photograph? N={bob,tim,david,cathy,evelyn,alan,bill}

Answer 1

There are 7 members, and we want to take a picture of them. But if Alan shows up first, it is not the same that Alan shows at last. So we have that the ways we could organize are:

$7\cdot6\cdot5\cdot4\cdot3\cdot2\cdot1=5040$