A cylindrical pencil sharpened at one edge is the combination of
a cone and a cylinder
frustum of a cone and a cylinder
a hemisphere and a cylinder
two cylinders
Step 1: Think of a new pencil before sharpening. Its body is in the shape of a cylinder (like a long pipe). A cylinder has two flat circular faces at the ends and a curved surface all around.
Step 2: When we sharpen one end, the wood and lead are cut to form a pointed tip. This pointed tip is shaped like a cone. A cone has a flat circular base and a curved surface that comes to a sharp point (called the vertex).
Step 3: So now the pencil is made of two parts joined together: - The cylindrical body (main length of the pencil). - The conical tip (sharpened part).
Final Answer: The pencil is the combination of a cone and a cylinder.