Question

If the area of a circle is $154c{m}^2$, then its perimeter is: $[\pi =\frac{22}{7}]$

• A. $22cm$
• B. $44cm$
• C. $50cm$
• D. $56cm$

Answer 1

The correct option is B $44cm$

Let the radius of circle be $r$ cm.

Now the area of circle$\Rightarrow \pi r^2=154{cm}^2$

$\Rightarrow \frac{22}{7}\times r^2=154{cm}^2$

$\Rightarrow r^2=\frac{154\times 7}{22}$

$\Rightarrow r^2=49$

$\Rightarrow r=7cm$

Perimeter of the circle$=$Circumference

$=2\pi r$

$=2\times \frac{22}{7}\times 7$

$=44cm$