11
There are 8*7/(2*1) = 28 combinations.
There are 21 combinations.
none
There are 9C2 = 9*8/(2*1) = 36 2-digit combinations.
11
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 8*7/(2*1) = 28 combinations.
11
There are 14C5 = 14*13*12*11*10/(5*4*3*2*1) = 2002
The number of combinations, denoted by 11C6 is 11!/[6!*(11-6)!] = 11*10*9*8*7/(5*4*3*2*1) = 462
You would get 4!/2! = 12 combinations.
There are 21 combinations.
none
There are 32C3 = 32*31*30/(3*2*1) = 4960 combinations. I do not have the inclination to list them all.
10 * * * * * That is just plain wrong! It depends on how many numbers in each combination but there are 1 combination of 4 numbers out of 4, 4 combinations of 3 numbers out of 4, 6 combinations of 2 numbers out of 4, 4 combinations of 1 number out of 4. A grand total of 15 (= 24-1) combinations.
There are 45 combinations.