A cone is placed inside a cylinder as shown. The radius of the cone is half the radius of the cylinder. The height of the cone is equal to the radius of the cylinder. What is the volume of the cone in terms of the radius, r?

Step-by-step explanation:
Volume of Cone
= 1/3 * (Base Area) * (Height).
Since the radius of the cone is r/2, we have
Base Area = π(r/2)² = πr²/4.
Also the height of the cone is r.
Hence Volume of Cone
= 1/3 * (πr²/4) * (r)
= πr³/12. (C)