Question

How do you find the radius of a circle from its circumference?

Answer 1

Solve for radius of the circle:

As the circumference of the circle $C$ is given by;

$\mathrm{C}=2\mathrm{\pi r}$, where $\mathrm{r}$ is the radius of the circle.

$\Rightarrow$$\frac{\mathrm{C}}{2\mathrm{\pi }}=\frac{2\mathrm{\pi r}}{2\mathrm{\pi }}$

$\Rightarrow$ $\frac{\mathrm{C}}{2\mathrm{\pi }}=\mathrm{r}$

Hence, the radius of the circle can be find out by dividing its circumference by $2\mathrm{\pi }$.