Find the circumference of the circle with diameter 10 units.

 

Concept: To calculate the circumference of a circle, we must first determine its diameter or radius. The appropriate value is then used in the equation.

Here, $diameter=10 units$ 

Now, 

$r=\frac{10}{2}=5 units$ 

Then, the circumference is,

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

$\Rightarrow C=2\mathrm{\pi }\times 5$

$\Rightarrow C=10\mathrm{\pi }$

Hence, the circumference of a given circle is  $10\mathrm{\pi } \mathrm{units}$.