Answer:
210 combinations.
Step-by-step explanation:
We have 10 total digits (0-9) and we only use 4 at a time. We can use the permutation formula [tex]\frac{n!}{k!(n-k)!}[/tex], and plug in 10 for n and 4 for k. This is called:
n choose k.
Plug the values in, and we get 210 permutations for the password.
