@OscarCunningham I did, however the solutions I come up with have an incompatibility between the first column and the second row. For the first column you need (a/b)*c = 2 and for the second row you need (b*e) - f = 37, but the latter can only be achieved with a digit between 5 and 9 for b, which would make Oh wait. There's no reaso why a/b should be a positive integer. Damnit.