How many 3-digit passwords can be formed from the digits 0 through 9?

You can form either 1,000 or 750 3 digit passwords using the numbers 0 through 9. If you use numbers that can be repeated at least once, you can get up to 1,000 unique passwords. If you only use numbers that do not repeat at all, you get up to 750 unique passwords.

the answer to this question is 729 and dont worry i checked my answer here is how you do it 9 X 9 X 9 it is the correct way