The radius of the cylinder is r. The radius of the cone is half of t<span>he radius of the cylinder: r/2. </span>The height of the cone is equal to the radius of <span>the cylinder: r.
If the volume of the cone is </span>π r²h/3, and the radius of the cone is r/2, and the height of the cone is r, then: V = π × r² × h / 3 V = π × (r/2)² × r / 3 V = π × r²/4 × r <span>/ 3 V = </span><span>π r³/12</span>