Answer:
6 1/4 cups of flour
Step-by-step explanation:
First we can add up the amount of flour needed for the cake and the cookies:
3 3/4 + 8 = 11 3/4 cups
Since he only has 5 1/2 cups of flour, we can subtract 5 1/2 from 11 3/4 to get the amount of flour he needs.
11 3/4 - 5 1/2 = 11 3/4 - 5 2/4 = 6 1/4
