At first, we will change the feet to the yard because the cost of carpet is per square yard
Since 1 yard = 3 feet, then
Divide each dimension by 3 to change it from feet to yard
Since the length of the room = 24 feet, then
The length of the room = 24/3 = 8 yards
Since the width of the room = 15 feet, then
The width of the room = 15/3 = 5 yards
The rule of the area of the rectangle is
Area = Length x width, then
The area of the room = 8 x 5 = 40 square yards
Since we will add extra 4 square yards to it, then
The total area needs to cover = 40 + 4 = 44 square yards
Since the cost of 1 square yard = $36, then
Multiply the area by the cost to find the cost of the carpet
The total cost = 44 x 36 = 1584
The cost of the carpet is $1584