The Volume of a Compound Solid
The figure consists of a cylinder and a cone, both with the same radius of r=5.4 ft. The height of the cylinder is h=7.7 ft and the total height (of cone and cylinder) is H = 16.7 ft. This means the height of the cone is hc = 16.7 - 7.7 = 9 ft.
The volume of a cylinder of height h and radius r is:

The volume of a cone of height hc and radius r is:

Calculate the volume of the cylinder:

Calculate the volume of the cone:

Now we add both volumes:
V = 705.388 + 274.827 = 980.215 cubic feet
Rounding to the nearest tenth:
V = 980.2 cubic feet