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
There are 6C3 = 20 such combinations.
There are 5,461,512 such combinations.
How about: 1+2+3+20 = 26 out of many other combinations
There are 8145060 combinations.
Precisely 1. For ANY number n, the number of combinations of n of those items is always 1.
You can make 5 combinations of 1 number, 10 combinations of 2 numbers, 10 combinations of 3 numbers, 5 combinations of 4 numbers, and 1 combinations of 5 number. 31 in all.
There are 24C12 = 24!/[12!*12!] = 2,704,156 combinations.
4*3*2*1 = 24 different combinations.
There are 13,244 of them.
55C6 = 28,989,675
55C6 = 28,989,675