45
3 x 3 x 3 x 3 = 81 combinations
10,000.
5040, assuming none of the digits are the same. (Assuming they're not, there's 5040 unique combinations you can make out of 7 digits).
9999
Assuming no duplication or repetition, 720
10
3 x 3 x 3 x 3 = 81 combinations
10,000.
5040, assuming none of the digits are the same. (Assuming they're not, there's 5040 unique combinations you can make out of 7 digits).
6
45 In combinations, the order of the digits does not matter so that 12 and 21 are considered the same.
9999
Only one.
Assuming no duplication or repetition, 720
Assuming the digits cannot be repeated, there are 7 combinations with 1 digit, 21 combinations with 2 digits, 35 combinations with 3 digits, 35 combinations with 4 digits, 21 combinations with 5 digits, 7 combinations with 6 digits and 1 combinations with 7 digits. That makes a total of 2^7 - 1 = 127: too many for me to list. If digits can be repeated, there are infinitely many combinations.
To find how many counting numbers have four distinct nonzero digits that sum up to 11, we first identify all combinations of four distinct digits (from 1 to 9) that meet this criterion. The possible combinations of digits that add up to 11 are limited, and we can use combinatorial methods to list them. After identifying valid sets, we can calculate the permutations for each set (since the order of digits matters) to get the total count. Upon calculating, we find there are 24 valid combinations yielding 576 distinct numbers.
You can get only four combinations: They are: 11, 118, 119 and 1189. In a combination, the order of the digits does not matter.