Ratios of flour-egg-chicken? Simple breading
I'm not sure that's the answer you were looking for but maybe it'll be helpful:

Most cooks don't find a reason to measure breading ingredients. 

A bowl of eggwash will give you the same coating wether two or twenty eggs are beaten in it. Two beaten eggs and two tablespoons of water go a long way and are usually enough. And the same goes for flour and breadcrumbs: The amount in the bowl doesn't determine the thickness of the coating. It's your hands that do it.

If you're just talking about economy, then allow me to suggest a trick I've seen in restaurants' kitchens: Use more flour and crumbs than you need, and after you're done strain them through a sieve. Pieces touched by eggs will clump and be strained out, and clean flour and crumbs will return to the fridge.