Because your baking trays can hold exactly one dozen cookies, you will produce and sell cookies by the dozen. should you give discounts for people who order two dozen cookies, three dozen cookies or more? if so, how much? will it take you any longer to fill a two-dozen cookie order than a one-dozen cookie order?

If you were to make more than a dozen cookies assuming that you can't bake them on separate cookie sheets at the same time than of course it will take longer to fill than one-dozen, but even with a discount you are making more of a profit than just selling one-dozen. Keeping the discount to a minimum is key, so possibly offering just 10% orders over one dozen cookies.