Answer:
1/4 bag for each batch.
Step-by-step explanation:
Start with 4 bags. If the cake requires 1/4 bag, then 3 3/4 bags of flour are left over for the cookies. That's rather a nice number when you are dealing with 15 batches of cookies.
Start by changing the 3 3/4 into a decimal.
3 3/4 = 3.75
Now divide 3.75 by 15
3.75 / 15 = 0.25 bags which is 1/4 bag. You only have to come up with one value so this one will do.
