We need to know how many digits the number is and if we can allow repeats. I will do this problem assuming 3 digit numbers and allowing repeats. Then there are 3 choices for each digits and 3x3x3=27 words of length 3. If we want to consider words of length 2 also, add 9 and of length 1 add 3 and for 0, we use none of them. So there are missing details we need to be sure we are doing the problem correctly. It all depends on exactly what is being asked!
about 13
210
There are 5*4*3 = 60 such numbers.
321 312 213 231 123 132 6 3 digit numbers.
You can make 4*3*2/2 = 12 numbers.
24
2233 2323 2332 3232 3223 3322
6*5*4*3=360
Six.
120 5-digit numbers can be made with the numbers 12345.
-- If the same digit may be repeated, then 64 can be made. -- If the same digit may not be repeated, then 24 can be made.
24