Question

Employees at a company are given a three digit employee identification code. If each digit cannot be repeated, how many different codes are possible?

Answer 1

720 codes.



There are 10 digits possible for the first digit of the code.

Since there can be no repeated digits, you subtract 1 and find there are only 9 possible digits for the second digit in the code.

Finally, subtract 1 again to find there are only 8 possible digits for the last digit.

Multiply these together to find the number of combinations.

10 * 9 * 8

90 * 8

720

So, there are 720 combinations if digits cannot be repeated.