A spherical balloon with radius r inches has volume V(r) = 4 3 πr3. Find an expression that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r + 2 inches.

Question

A spherical balloon with radius r inches has volume  V(r) =  4 3 πr3.  Find an expression that represents the amount of air required to inflate the balloon from a radius of r inches to a radius of r + 2 inches.

akashdeepdeb · Answer

I am just curious, do you know differentiation? 
There are many ways to solve this. :)

anonymous · Answer

True @AkashdeepDeb

akashdeepdeb · Answer

Okay, if you do not know it. 

Just find the difference between the volumes of the sphere when the radius if 'r' and when the radius is 'r+2' because, that's how you'll get an expression for the amount of air (volume of the air) required to fill the balloon to a radius of 'r+2'.

Getting this? :D