Question

What is the surface area to volume ratio of a sphere?

Answer 1

Surface area to volume ratio of a sphere equals to `3/r`, where `r` is the sphere's radius.

Explanation:

Surface area of a sphere with radius `r` equals to `4pir^2`.
The volume of this sphere is `4/3pir^3`.
Ratio of the surface area to volume, therefore, equals to

`(4pir^2)/(4/3pir^3)=4(3/4)(pi/pi)(r^2/r^3)=3/r`