There is a coin. Ram attaches a conical attachment to one flat end of coin. The conical attachment has same radius as coin. What is the surface area of the combined solid?
Coin base area + Coin C.S.A + cone C.S.A
This leaves only the following surfaces for the combined solid-
1. One flat surface of coin
2. Curved surface of coin
3. Curved surface area of cone
These 3 areas add up together to give total surface area of combined solid.