Sam has nine flower pots, and want to display four of them on the front porch in a row, and the other five in a second row. (The order of the pots matters.) How many different displays are possible?
For the first row, we want to choose any 4 of the 9 pots and arrange them in 4! ways
So this is C(9,4) * 4! = 3024
For the second row, we can arrange any of the 5 remaining pots in 5! ways = 120 ways
So.....the total arrangements are
3024 * 120 =