All of them, but it does depend on what operators are allowed.
4!=4x3x2x1=24
24 ways
456,976,000
You may notice that card from a certain institution all have the same first four number. how many different credit card numbers can this institution create.
1
The four digits can be used to produce infinitely many different numbers if repetition is permitted. Without repetition, there are 24 possible numbers. A lot more can be produced if the numbers are combined using binary oprations, fore example, 19 * 8/4 = 19*2 = 38.
3*3*2*1 = 18 of them.
If the digits are all different then 18. Otherwise, 192.
any 4 from 7 is 35, in any order is 35 x 24 ie 840
Oh, what a happy little question! With four 2's, you can create many numbers through addition, subtraction, multiplication, and division. Let's paint a few numbers together: 2+2+2+2=8, 2x2x2x2=16, and (22)/(2)+2=13. Just remember, there are no mistakes, only happy little calculations!
Only four numbers:20233032
Oh, dude, I mean, like, there are 4 digits in 1230, right? So you can totally make 4-digit numbers by using each of those digits once. That's like, 4 factorial, which is 24. So, you can totally write 24 different four-digit numbers using 1230 without repeating any digit. Easy peasy!