How many possible 4-digit numbers are there?

Answer by  somethingcute (15)

There are a possibility of 10,000 different four digit numbers, assuming you may repeat the same digit. To get 10,000, you multiply 10 (number of choices for the first digit) times 10 (choices for the second digit) times 10 (choices for the third digit) times 10 (choices for the fourth digit). If you didn't repeat, there would be 5,040 possibilities.

Answer by  Redav (231)

Assuming you can use 0 to left there are 10000 numbers. If not there 9000 numbers because 1000 numbers that are between 0 and 999 and they are taken off.