Answer:
She needs an additional 24 feet of fabric.
Explanation:
In order to solve this problem we first need to calculate how many yards of fabric Patricia needs. This will be given by the sum of the fabric needed for the curtains and the fabric required to cover the storage bench. As seen bellow:
required fabric = 10 + 3 = 13 yards
We need to convert this value to feets, so the units are the same. To do that we multiply by 3.
required fabric = 13*3 = 39 feet
To know how many more fabric she needs we have to subtract the required fabric for the task by the total she already has. This is shown bellow:
needed fabric = 39 - 15 = 24 feet
She needs an additional 24 feet of fabric.