Not repeating, it is 7*6*5*4 which is 840 ways
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There are 7 choices for each of four digits, right?
74 = 2401
If each can be used again, it is 7x7x7x7 or 2401 combinations. If not it is 7x6x5x4 or 840 combinations
120 combinations using each digit once per combination. There are 625 combinations if you can repeat the digits.
1,000. The list looks just like the counting numbers from 000 to 999 .
There are 9999 possible combinations starting from 0000 to 9999
There are 15, and they are:1234 1235 1236 1245 1246 1256 1345 1346 1356 1456 2345 2346 2356 2456 3456.
if its not alphanumeric, 999999 variations
Number of 7 digit combinations out of the 10 one-digit numbers = 120.
There are 840 4-digit combinations without repeating any digit in the combinations.
120 combinations using each digit once per combination. There are 625 combinations if you can repeat the digits.
9
-8
There cannot be such a number.
It depends. If you can only use each number once, there are 720 combinations. If you can use numbers multiple times, then there are 1000 combinations, by using all numbers from 000 to 999.
It is: 9C7 = 36
66
15
10,000
it depends on which 8 numbers your talking about