What is the value of 9p5?
a. 45
b. 126
c. 15,120
d . 59,049
a cooking club has 12 members. how many ways can they select a president and vice president from among the members?
a. 1320
b. 220
c. 132
d. 66

The correct answers are:
C) 15120
C) 132.

Explanation:
9P5 is a permutation of 9 objects taken 5 at a time; this is
9! / (9-5)! = 9!/4!
                = (9*8*7*6*5*4*3*2*1)/(4*3*2*1)
                = 15120.

The second question is a permutation of 12 objects taken 2 at a time; this is 12! / (12-2)! = 12!/10!
                    =(12*11*10*9*8*7*6*5*4*3*2*1) / (10*9*8*7*6*5*4*3*2*1)
                    =132