Question

A right circular cylinder just encloses a sphere in it of r as radius find
1. surface area of sphere .
2. CSA of cylinder
3. Ratio of (1) and (2).

Answer 1

surface area of sphere

Answer 2

here 'r' i.e. radius is common for both cylinder and sphere

so the surface are of spere = 4πr^2

curved surface area of cylinder = 2πrh - 4πr^2

and ratio is found by dividing them