how many combinations of four digits are there?

Answer 1

if no number goes two times
it would be 4*4*4*4
if not
4*3*2*1

Answer 2

If you are referring to how many 4 digit sequences can you have using the numbers 0 through 9, then the answer is 10,000.

You get this from 10^4. 10 possible choices for each digit.

If you mean how many ways can you rearrange 4 unique digits, you get 24.

you four choices for the first number, then you'll have 3 choices for the last number, 2 choices for the third number, and only one digit left for the last one.

In other words, 4 * 3 * 2 * 1.

Whenever you do combinations, it's best to look at how many choices you have for the first digit, how many choices you have left for the next, and so on multiplying them all together.

Answer 3

You can work with 4 digits, where each digit can be any of the following 10: 0,1,2,3,4,5,6,7,8,9
In other words, there would be 10*10*10*10 = 10000 possible combinations of 4 digits.

The answer would not be 10! because each value (from 0 - 9) is reusable for each of the 4 digits, and the answer would not be 4! because we have more than 4 values per digit to work with (we have 10; zero to nine).

Answer 4

if it is a four digited number and u need the no. of ways of arranging it,
we have 9*10^3 = 9000 ways.

If it is a combination of 4 digits and u just want the no. of ways to arrange them, Then it can be done in
4! = 24 ways (without repeating any of the digits)
4^4=256 ways (by repeating any no. of digits).

Answer 5

You're actually asking about permutations, not combinations. The number of possible orderings of four unique objects is
4! = 4*3*2*1 = 24

Answer 6

Combination of 4 digits= 4! (read: four factorial)

4x3x2x1=24

Answer 7

With repeating digits: 10,000

Answer 8

10000