Two make combinations you would take 2x1=2 combinations only
42 combinations.
There are 30 different combinations if the order in which the books were chosen counts, so a set of book A and book B is considered different from a set of book B and book A. There are 15 different combinations if it does not matter in which order the books were chosen, so a set of book A and book B is considered the same as a set of book B and book A.
If the 6 digits can be repeated, there are 1296 different combinations. If you cannot repeat digits in the combination there are 360 different combinations. * * * * * No. That is the number of PERMUTATIONS, not COMBINATIONS. If you have 6 different digits, you can make only 15 4-digit combinations from them.
one hundred and twenty
The number of 4 different book combinations you can choose from 6 books is;6C4 =6!/[4!(6-4)!] =15 combinations of 4 different books.
Two make combinations you would take 2x1=2 combinations only
20 different combinations of silverware
25 different combinations.
42 combinations.
18
The question is too broad. There are many different books for piano with many different combinations of ABBA songs.
There are 30 different combinations if the order in which the books were chosen counts, so a set of book A and book B is considered different from a set of book B and book A. There are 15 different combinations if it does not matter in which order the books were chosen, so a set of book A and book B is considered the same as a set of book B and book A.
If the 6 digits can be repeated, there are 1296 different combinations. If you cannot repeat digits in the combination there are 360 different combinations. * * * * * No. That is the number of PERMUTATIONS, not COMBINATIONS. If you have 6 different digits, you can make only 15 4-digit combinations from them.
a lot
6 ways
one hundred and twenty