Question

If the perimeter of a semi-circle is $36cm$. What will be its diameter?

• A. $88cm$
• B. $22cm$
• C. $28cm$
• D. $14cm$

Answer 1

The correct option is D $14cm$

Perimeter of semicircle$=36cm$

$\pi r+d=36$

$\Rightarrow \pi r+2r=36$

$\Rightarrow r(\frac{22}{7}+2)=36$

$\Rightarrow \frac{36}{7}\times r=36$

$\Rightarrow r=7$

$\therefore$ Diameter $2r=2\times 7=14cm$