Store $$A$$ and Store $$B$$ had an equal number of packs of potato chips at first. After Store $$A$$ sold $$290$$ packs of potato chips, Store $$B$$ had $$3$$ times as many packs of potato chips as Store $$A$$. How many packs of potato chips did both stores have altogether at first? 
Overseas Competition->Knowledge Point->Counting Modules