Question

If the perimeter of a semi-circle is 144 cm, then the area of the semi-circle is $1232c{m}^2$.

• A. True
• B. False

Answer 1

The correct option is A

True

Given, perimeter of a semi-circle = 144 cm
Let $r$ be the radius of the semi-circle.
$\Rightarrow r(\pi +2)=144$
$\Rightarrow r(\frac{22}{7}+2)=144$
$\Rightarrow r\left(\frac{22+14}{7}\right)=144$
$\Rightarrow r\times \frac{36}{7}=144\Rightarrow r=28cm$
Area of semi-circle
$=\frac{1}{2}\pi r^2=\frac{1}{2}\times \frac{22}{7}\times 28\times 28$
$=1232c{m}^2$