Repetition Examples

Password: 8 characters, each from 26 lowercase letters. Count = 26^8 ≈ 208 billion.

Binary string of length 10. Each position is 0 or 1. Count = 2^10 = 1024.

If letters can repeat, the formula is always n^r. If they can't, use P(n,r) = n!/(n-r)!.