**1. A/B=3 **

2. C/D=9 In both problems ( 1. and 2.) the union of the digits of numbers

** A & B (or C & D)** is the full set of 9 non-zero decimal digits.

List all existing solutions.

I think that this needs further clarification.

Part part 1, is 41152263 / 123456789 a valid solution? If so, then there are an infinite number of solutions.

What if a number does not repeat within the numerator or denominator, but the same digit appears in both? I think this is a solution, since the union of {1,2,3,4,5} and {5,6,7,8,9} is {1,2,3,4,5,6,7,8,9}. And this is consistent with a finite number of solutions.