Find the perimeter (in $\text{cm}$) of a semicircle of radius $14\text{cm}$.

The perimeter of a semicircle includes the curved arc length ($\pi r$) and the straight diameter ($2r$):
$$\text{Perimeter}=\pi r+2r=r(\pi +2)$$
Given radius $r=14\text{cm}$ and taking $\pi =\frac{22}{7}$:
$$\text{Perimeter}=14\times \left(\frac{22}{7}+2\right)$$
$$\text{Perimeter}=14\times \left(\frac{22+14}{7}\right)=14\times \frac{36}{7}=2\times 36=72\text{cm}$$