Final answer:
Lucy used 1/15 cup of sugar to make one brownie, by dividing the total sugar used, 8/5 cups, by the number of brownies made, which is 24.
Step-by-step explanation:
To find out how much sugar Lucy used to make one brownie, we can divide the total amount of sugar she used by the total number of brownies she made. Lucy used 8/5 cups of sugar to make 24 brownies. By setting up a simple division, we get:
Amount of sugar per brownie = Total amount of sugar / Number of brownies
= (8/5) cups / 24 brownies
= 1/15 cup of sugar per brownie.
This is the amount of sugar Lucy used for making one brownie.