## Algebra 1: Common Core (15th Edition)

(a) First of all Find $4P_{4}$ Write it by using factorials: $4P_{4}=\frac{4 !}{4-4}!$ Simplify: $4P_{4}=\frac{4!}{0!}=\frac{4.3.2.1}{1}$ $4P_{4}=24$ Thus, there are 24 possible permutations. (b) No, especially if your name is very short like in part (a) as it is more prone to hackers since there are only a number of possible passwords using your name.