Question

In the fig., PSR RTQ , and PAQ are three semicircles of diameters 10 cm, 3 cm and 7 cm region
respectively. What is the perimeter of shaded region?
Use 7
22 p = .
(a) 62 1. cm2
(b) 92 1. cm2
(c) 31 4. cm2
(d) 12 4. cm2

Answer 1

Answer:

Radius of semicircle PSR=

2

1

×10=5cm

Radius of semicircle RTQ=

2

1

×3cm=1.5cm

Radius of semicircle PAQ=

2

1

×7=3.5cm

Perimeter of shaded region = Circumference of semicircle PSR+ Circumference of semicircle RTQ+ Circumference of semicircle PAQ

Threfore,

Perimeter of shaded region =π×5+π×1.5+π×3.5=10π=31.4