$$A$$ and $$B$$ are two distinct $$3-$$digit numbers which have two equal digits (not necessarily in the same number place). It is known that the highest common factor of $$A$$ and $$B$$ is $$75$$. Find the largest possible sum of $$A$$ and $$B$$. 
Overseas Competition->Knowledge Point->Number Theory Modules->Factors and Multiples->Common Factors and Common Multiples