The surface area of a sphere is $616{\text{cm}}^2$. Find its radius.Take $\pi =\frac{22}{7}$.

We know that, the surface area of a sphere$=4\pi r^2$

Here, $4\pi r^2=616$

$\Rightarrow 4\times \frac{22}{7}\times r^2=616$

$\Rightarrow r=7\text{cm}$

Hence, the radius of the sphere is $7 \text{cm}$.