Question

The above Fig. 12.79 is formed by four semi-circular pieces of wire, each of diameter 10 cm. The

area enclosed is:

(A) 82 cm (B) 150 cm? 100 cm

(D) 80 cm.​

Answer 1

Circumference = 39.6 cm

We know:

Circumference of a circle = 2πr

⇒39.6 =2×227×r⇒39.6×72×22=r⇒r=6.3 cm

Also,

Area of the circle = πr2

                             =227×6.3×6.3=124.74 cm2