how many 4 digit numbers can be made with the digits 1-9?

Answer 1

If you can repeat the digits (ie. have numbers like 4477 and 4444) then its 9 to the power of 4 (9*9*9*9) or 6561.

If not, it's 9*8*7*6, or 3024.

Answer 2

3024 4-digit numbers can be made. Here is how you solve it:
we need 4 digits so here they are _ _ _ _
for the first digit you have 9 numbers you could place, which leaves 8 numbers for the 2nd digit, 7 numbers for the 3rd digit and 6 numbers for the 4th digit.
so you multiply 9.8.7.6 = 3024

A way to prove this method is this:
lets say that the question asked us how many 3 digit numbers can be made wşth the digits 1-3. My method tells us that 3.2=6 numbers can be made. Lets check it
123, 132, 231, 213, 312, 321
As you see you can't make more than 6 numbers. I hope this answered your question.
If you can repeat the numbers your anwer would be 9.9.9.9

Answer 3

There is 21 combinations of 4 digit numbers you can make using 1 - 9 assuming you are using each digit only once.

Answer 4

If you are allowing repeats of the 9 numbers, you can have 9^4 possibilities.

If no repeats of the numbers from 1-9 are allowed, you can have (9 * 8 * 7 * 6) = 3024 possibilities

Answer 5

the posibility of a first, second, third and fourth might be from 1 to 9...so

9 X 9 X 9 X 9 = 6561 ways

Answer 6

9*9*9*9=6561

Answer 7

3024.
you multiply 9x8x7x6