Because of this, the designer of this question, did so quite poorly. Now simplistically we could say that the domain would be [0,+oo) and the range [0,+oo), But this would be ignoring all of the above. In reality the domain would be [0, 1/24, 2/24, etc n/24] where n/24 was some real limitation on the amount of flour (and time) that you could possibly have and the range would be [0,1,2,3,…n] where n would be the result of the the limited domain values. (unless we were making fractional cookies :P)
Sorry, I could not resist, I cringe when I see subjective math problems. The range and domain I put is what I would call “reasonable” range and domain. I wonder what the designer of the question thinks is reasonable….