Question

Aaron is making 3 1/2 batches of brownies. Each batch takes 2 1/2 cups of flour. How much flour will John need for the brownies?

Answer 1

1 batch=2 1/2 cups of flour
3 1/2 batches= x cups of flour

    1batch              3 1/2 batches        
___________ = _____________
  2 1/2 cups               x cups

Cross multiply
1x=8 3/4
divide both sides by 1
x=8 3/4 cups

Answer= 8 3/4 cups of flour

Answer 2

Since each batch takes
2 1/2 cups and he's making 3 1/2 batches,
You multiply the two numbers. First change them into improper fractions.
2 1/2 = 5/2
3 1/2 = 7/2
5/2 * 7/2 = 35/4
Simplify 8 3/4 cups flour