Question

The radius of a semicircular garden is 21 m. One has to walk ____ m to walk all around the garden once.

• A. 110
• B. 108
• C. 170
• D. 180

Answer 1

The correct option is B 108

As the garden is in a semicircular shape, therefore,

Radius of garden $=21m$

As we know that,

Circumference of semicircle $=\pi r$

Whereas, $r$ is the radius

Distance to walk all around the ground $\left(d\right)=\pi r+2r$

$d=\frac{22}{7}\times 21+2\times 21$

$\Rightarrow d=66+42=108$

Hence one has to walk $108m$ to walk all around the garden once.

Hence the correct answer is $\left(B\right)108m$.