Question

A piece of wire of length 108 cm is bent to form
a semicircular arc bounded by its diameter.
Find its radius and enclosed area.​

Answer 1

Answer:

Length of wire = 108 cm

Let r be the radius of the semicircle

πr+ 2r = 108

⇒ r(π + 2) = 108 ⇒ r = ((22/7) + 2) = 108

⇒ (36/7)r = 108 ⇒ r = (108 × 7)/36 = 27 cm

Area = πr2 /2 = (22/(7 × 2)) × 21 × 21 = (1386/2) cm2

= 693 cm2