Question

When the perimeter of semi circular field is 108 metres then find the radius

Answer 1

Answer:

Radius = 42cm

Step-by-step explanation:

Let the radius be r cm

Perimeter = 108cm

⇒$\frac{1}{2}(2\pi r)+2r=108$

⇒$\pi r+2r=108$

⇒$\frac{22}{7}×r+2r=108$  [$\pi=\frac{22}{7}$]

⇒$36r=108×7$

⇒$r=3×6=21$

∴Radius =2r=(2×21)cm=42cm