The volume of a cylinder is 81 cubic feet. What is the volume of a cone that fits exactly inside the cylinder? Provide an explanation and proof for your answer.
V ( cylinder ) = r² π h V ( cone ) = 1/3 r² π h A cone that fits exactly inside the cylinder has the volume: V ( cone ) = 1/3 V ( cylinder = 1/3 · 81 = 27 ft³