17,576 possible combinations
* * * * *
Not quite! This is the total number of permutations of 3 letters out of 26. AAB is counted as being different from ABA or BAA. But these are the same combinations.
Thus there are 26 combinations of just one letter.
26*25 combinations of two letters and
26*25*24/(3*2*1) of three.
In all, that makes 26 + 650 + 2600 = 3276
The answer is 10C3 = 10*9*8/(3*2*1) = 120 combinations.
4*3*2*1 = 24 different combinations.
Just 4: 123, 124, 134 and 234. The order of the numbers does not matter with combinations. If it does, then they are permutations, not combinations.
Taking this bit by bit... For each number there are 10 possibilities so three numbers has 10^3 which is 1000 for each letter there are 26 choices, so for three letters you have 26^3 which is 17576 together there are 17576 * 1000 options which makes 17576000 possible combinations of letters and numbers and I suspect that is what you want. However if the order of the combination is important you must take into account the position of each letter/number and remove duplicate combinations. Good luck with that
As there are 26 letters in the alphabet. You can calculate the number of combinations by multiplying 26x26x26, giving you the answer 17576.
You did not give us the set to work with...
There are: 35C3 = 6545 combinations
3,124,550 possible combinations
256 iThink * * * * * It depends on combinations of how many. There is 1 combination of 4 letters out of 4, 4 combinations of 3 letters out of 4, 6 combinations of 2 letters out of 4, 4 combinations of 1 letter out of 4. Than makes 15 (= 24-1) in all. Well below the 256 suggested by the previous answer.
There are 6C3 = 20 such combinations.
There are 5C3 = 10 combinations.
2600
4
You could make 10*10*10*26*26*26 combinations, or 17576000 combinations.
There are 9C3 = 84 combinations.
8
There are 32C3 = 32*31*30/(3*2*1) = 4960 combinations. I do not have the inclination to list them all.