45
I assume you mean how many 4-digit numbers can be made from a set such as {A,A, B, C} where A, B and C are single digits. There are 12 such numbers.
162
about 13
they are 24 you can make with the numbers 1-4 or any other 4 digits here they are123412431432142313421324213421432431241323412314312431423421341232413214423142134312432141324123* * * * *WRONG!These are permutations, not combinations. In a combination theorder of the digits does not matter so there is only one combination of 4 digits out of 4.
94
45
I assume you mean how many 4-digit numbers can be made from a set such as {A,A, B, C} where A, B and C are single digits. There are 12 such numbers.
6
There are 7,290 different 4-digit numbers that can be formed from the digits 1-9 without repetition.
about 13
they are 24 you can make with the numbers 1-4 or any other 4 digits here they are123412431432142313421324213421432431241323412314312431423421341232413214423142134312432141324123* * * * *WRONG!These are permutations, not combinations. In a combination theorder of the digits does not matter so there is only one combination of 4 digits out of 4.
Assuming you mean permutations of three digits, then the set of numbers that can be made with these digits is: 345 354 435 453 534 543 There are six possible permutations of three numbers.
9
10
10 digits are numbers in the billions.
1,956 different numbers can be made from 6 digits. You can calculate this by using the permutation function in a summation function, like this: Σ6k=1 6Pk = 6P1+6P2+...+6P5+6P6 What this does is calculate how many 1 digit numbers you can make from 6 digits, then how many 2 digit numbers can be made from 6 digits and adds the amounts together, then calculates how many 3 digit numbers can be made and adds that on as well etc.