Answer:
Kylee makes 6 1/2, or 6.5 cups of the cake mixture.
Explanation:
She uses double the cake mixture as water. She uses 3 1/4 cups of water, or 13/4 as an improper fraction, so she uses double that of cake mixture, which is 6 1/2, or 26/4 cups of cake mixture.
As a decimal that is 6.5.