evaluate the permutation?

Question

P (26, 15)

a) 8.419417829 x 10^17
b) 1.010 x 10^19
c) 6.476475253 x 10^16
d) 1.111 x 10^20

Answer 1

P (26, 15) = 26!/(26-15)! = 26!/11!
= 26x25x24x23x22x21x20x19x18 x17x16x15x14x13x12
b) 1.010 x 10^19

Answer 2

P(26,15) =
26!/(26-15)! =
26!/11! =
10,103,301,395,066,880,000.

That's approximately your answer (b), 1.010 x 10^19.

Answer 3

the second number tells us how many numbers we will multiply down to. we will start at 26 and decrease 1 at a time for 15 times.

p(26,15) = 26*25*24*23*.....13*12) = 1.01 * 10^19

choice b