Answer:
A)336
B) In how many ways can you arrange 8 people in 3 different chairs?
C) 21
D) You want to buy 3 cartoon books from a book store that has 7 cartoon books. In how many ways can you select?
Explanation:
A) P(n, r) = P(8, 3)
Formula for permutation is;
P(n, r) = n!/(n - r)!
P(8, 3) = 8!/(8 - 3)!
P(8, 3) = (8 × 7 × 6 × 5!)/5!
5! will cancel out to give;
P(8, 3) = (8 × 7 × 6)
P(8, 3) = 336
B) In how many ways can you arrange 8 people in 3 different chairs?
C) C(n, r) = C(7, 2)
Formula for combination is;
C(7, 2) = n!/(n - r)!r!
Thus;
C(7, 2) = 7!/(7 - 2)!2!
C(7, 2) = (7 × 6 × 5!)/(5! × 2 × 1)
5! will cancel out to give;
C(7, 2) = 7 × 6/2
C(7, 2) = 21
D) You want to buy 3 cartoon books from a book store that has 7 cartoon books. In how many ways can you select?