At Central Middle School the 108 students who take the AMC meet in the evening to talk about problems and eat an average of two cookies apiece. Walter and Gretel are baking Bonnie's Best Bar Cookies this year. Their recipe, which makes a pan of 15 cookies, list these items:

Question

1 1/2 cups of flour

2 eggs

3 tablespoons butter

3/4 cups sugar

1 package of chocolate drops.

They will make only full recipes, no partial recipes.

Walter and Gretel must make enough pans of cookies to supply 216 cookies. There are 8 tablespoons in a stick of butter. How many sticks of butter will be needed? (Some butter may be left over, of course.)

Answer 1

To make 15 cookies, Walter and Gretel need 3 tablespoons of butter. Since they need to make 216 cookies, they will need to make 216/15 = 14.4 pans of cookies.

Each pan of cookies requires 3 tablespoons of butter, so in total they will need 14.4 * 3 = 43.2 tablespoons of butter.

Since there are 8 tablespoons in a stick of butter, they will need 43.2/8 = 5.4 sticks of butter.

Therefore, Walter and Gretel will need 6 sticks of butter to make enough pans of cookies to supply 216 cookies.