233 = 18 combinations.
3 items each in 3 categories gives 3*3*3 = 27 possible combinations.
11*3*3 = 99 combinations.
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233 = 18 combinations.
There are 6C3 = 20 such combinations.
There are 5C3 = 10 combinations.
3 items each in 3 categories gives 3*3*3 = 27 possible combinations.
11*3*3 = 99 combinations.
You could make 10*10*10*26*26*26 combinations, or 17576000 combinations.
There are 9C3 = 84 combinations.
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There are 32C3 = 32*31*30/(3*2*1) = 4960 combinations. I do not have the inclination to list them all.
3 x 3 x 3 x 3 = 81 combinations
I am assuming you mean 3-number combinations rather than 3 digit combinations. Otherwise you have to treat 21 as a 2-digit number and equate it to 1-and-2. There are 21C3 combinations = 21*20*19/(3*2*1) = 7980 combinations.