Chapter 12 - Data Analysis and Probability - 12-6 Permutations and Combinations - Practice and Problem-Solving Exercises - Page 754: 24

79833600

Use the formula of permutation: $_{n}$P$_{r}$=$\frac{n!}{(n-r)!}$. Plug in 12 for N and 9 for R: $_{n}$P$_{r}$=$\frac{n!}{(n-r)!}$ $_{12}$P$_{9}$=$\frac{12!}{(12-9)!}$ -simplify- $_{12}$P$_{9}$=$\frac{12!}{3!}$ -write using factorial- $_{12}$P$_{9}$=$\frac{12*11*10*9*8*7*6*5*4*3*2*1}{3*2*1}$ -simplify- $_{12}$P$_{9}$=79833600