Question

Laura is baking a cake. The recipe says that she has to mix 64 grams of chocolate powder to the flour. Laura knows that 1 cup of that particular chocolate powder has a mass of 128 grams. She added 2/3 cups of chocolate powder to the flour. Should Laura add more chocolate powder to make the exact recipe, or did she go over and by what amount?

Answer 1

To make 1 recipe, Laura needs
(64 grams)/(128 grams/cup) = (1/2) cup

2/3 cup is more than 1/2 cup, so Laura went over by the amount of
2/3 c - 1/2 c = 4/6 c - 3/6 c = 1/6 c