Ok, I see where you are misunderstanding what I am saying.

This wouldn't be on a building by building basis. It would, as you want it to, be as buildings as a whole. I was just using a single building because it simplified the description.

So, following on from my example:

If you had 1,000,000 buildings that in total requyiered 100,000,000 uneducated workers, 50,000,000 educated workers and 3,000,000 university workers, then my example still holds.

This would enable you to work out how efficient your work force is. IF you have too few workers, then your buildings won't be as effective, however, if you have too many workers, you will be paying too much for the amount of work being done. Therefore the player ends up having to balance their work force to get the best out of them.

It doesn't matter how many workers are needed in total, you can work it out with large numbers just as well as with small numbers, and it doesn't matter how many buildings you have, as you are just working off totals.