Answer: 7 7/8 cups of flour
Explanation:
Since John is making 3 1/2 batches of cookies and each batch takes 2 1/4 cups of flour.
The amount of flours that John will need for the cookies will be gotten by multiply the batches of cookies made by the number of flours of cups used per batch and this will be:
= 3 1/2 × 2 1/4
= 7/2 × 9/4
= 63/8
= 7 7/8 cups of flour