Have to bake a lot of brownies to sell! you have plenty of flour, cocoa, milk, and oil, but you only have 6 1/2 sticks of butter. you need to know how many batches of brownies you can bake, based on your limited amount of butter. you can cook partial batches in order to use up every bit of butter, which will also you to bake the most brownies possible. each batch needs 3/4 of a stick of butter.

8 + 2/3 batches of brownies you can bake.

Step-by-step explanation:

6 1/2 butter  = 6 + 1/2 = (2·6 + 1)/2 = 13/2 sticks of butter, we have this

Since we have 13/2 sticks of butter and each batch of brownies needs 3/4 of a stick of butter, we have to divide the amount of butter we have between the amount of butter we use to bake a batch of brownies.

13/2 butter ÷ 3/4 butter/batch = 13·4/2·3 batches = 52/6 batches = 8 + 2/3 batches

8 + 2/3 batches of brownies you can bake.