a, b, c have 9 nonzero digits with each of them appearing exactly once. The smallest possible number: 123 The last digit of c should be a multiple of 5 ending in 5, so the first digit of a should end in an odd digit (3, 7, or 9). The first digit of a should be 1 because if it were larger, then c would be four digits. Process of trial and error:

a: b: c =1: 3: 5 = 123: 369 : 615 3 and 6 repeated

a, b, c have 9 nonzero digits with each of them appearing exactly once. The smallest possible number: 123 The last digit of c should be a multiple of 5 ending in 5, so the first digit of a should end in an odd digit (3, 7, or 9). The first digit of a should be 1 because if it were larger, then c would be four digits. Process of trial and error:

a: b: c =1: 3: 5 = 123: 369 : 615 3 and 6 repeated