Question

If the surfabe areas of two spheres are in ratio 9 : 16 then find the ratio of their radii

Answer 1

surface area of sphere=
$4\pi {r}^{2}$
let their radius be r and R
so
4 pie r^2/4 pie R^2= 9/16
r^2/R^2= 9/16
r/R=
$\sqrt{9} \: \: \div \sqrt{16}$
r/R=3/4
ratio = 3:4