If one and a half chickens lay one and a half eggs in one and a half days, how long would it take two chickens to lay 32 eggs?

We assume the work the chickens do per egg is a constant.
  (1.5 chickens)·(1.5 days)/(1.5 eggs) = (2 chickens)·(d days)/(32 eggs)
  16·1.5 = d . . . . . multiply by 16 eggs/(chickens·days)
  d = 24

It would take 2 chickens 24 days to lay 32 eggs.