Question

if the radius of a sphere is doubled then what is the ratio of their surface area ​

Answer 1

Step-by-step explanation:

Surface area of sphere=4πr²

If radius is double =2×r

=2r

surface area of sphere(radius double)=4π2r²

ratio of surface area=4πr²÷4π2r²

=1÷2

Hence,ratio of surface area=1:2