Answer:
15P3 = 15!/ (15-3)! = 15*14*13*12! / 12! = 15*14*13
Step-by-step explanation:
When the seats are empty, there are a total of 15 people that can possibly sit in there. There will only be 1 person left.
When the 1st seat is taken there are now 14 people who can possibly sit on another chair. Same goes when 2 seaats are taken.
To find the total number of possibilities, we multiply together the possible number of people for seat 1, seat2, and seat 3.
Or, if we use stat, nPr = n! / (n-r)!
Meaning:
15P3 = 15!/ (15-3)! = 15*14*13*12! / 12! = 15*14*13
