📦 Mensuration

Pick a 3-D shape and change its size — watch its surface area and volume update instantly!

Surface Area

Volume

🧠 The Big Idea

Surface area is the total area of all faces/curved surfaces — the "wrapping paper". Volume is the space inside — the "filling".
Cube: SA = 6a², V = a³ · Cylinder: SA = 2πr(r+h), V = πr²h · Cone: V = ⅓πr²h · Sphere: SA = 4πr², V = 4/3πr³.
Mensuration answers real questions: paint for a wall, water in a tank, metal in a can. 🥫