The sandbox is to be only partially filled with sand. What is the total amount of sand needed to fill this sandbox so that the sand is 1 foot deep?
The sandbox is made up of two rectangles.
There is a big rectangle on the left, which is 8.5 ft long by 8 ft broad.
Then a small rectangle on the upper right, which is 2.5 ft by 4 ft.
For the 1st area, A1 = 8.5 * 8 = 76 sq ft
For the 2nd area, A2 = 2.5 * 4 = 10 sq ft
Total area is A = A1 + A2 = 76 + 10 = 86 sq ft.
The sandbox is to be filled to a height of 1 ft.
So total volume of the sand added will be,
Vol = A * 1 = 86 * 1 = 86 cu ft
Answer: Vol = 86 cu ft