This is a group of solids in which the volume is equal to one-third of the product of base area and altitude. There are two solids that belong to this group; the pyramid and the cone.
Like cylinder and prism, the name of pyramid and cone is according to the shape of the base. If the base is pentagon, the pyramid is called pentagonal pyramid, and if the base is circle, the cone is called circular cone. The formula for the volume of these solids is
Where Ab = area of the base, and h = altitude.