SSC CPO SI and ASI Model Paper 3

(3) Volume of a sphere $=\frac{4}{3}\mathit{\pi }{\mathit{r}}^3$
Let r1 and V1 be the radius andvolume of sphere 1 and ${\mathit{r}}_2$and ${\mathit{V}}_2$be the radius and volume of sphere2.
According to the question,
Volume of sphere 1 : Volume ofsphere 2 = 27 : 64
$\Rightarrow \frac{4}{3}\mathit{\pi }\mathit{r}{1}^3:\frac{4}{3}\mathit{\pi }\mathit{r}{2}^3=27:64$
$\Rightarrow \mathit{r}1:{\mathit{r}}_2=3:4$
Surface area of sphere $=4\mathit{\pi }{\mathit{r}}^2$
Required ratio = Surface area ofsphere 1 : Surface area of sphere 2
$\Rightarrow 4\mathit{\pi }{\mathit{r}}_1^2:4\mathit{\pi }{\mathit{r}}_2^2=9:16$