Q3 of 27 Page 228

Find the area of the shaded region in each of the following figures.

Diameter of bigger semicircle, D = 21 cm

⇒ Radius of bigger semicircle, R = D÷ 2



Diameter of smaller semicircle, d = 21 cm


⇒ Radius of smaller semicircle, r = d÷ 2





⇒ A1 = 173.25 sq.cm


Similarly,


⇒ A2 = 43.31 sq.cm


Area of shaded region = 2 × (A1 – A2)


⇒ Req. area = 2 × (173.25 – 43.31)


⇒ 2 × 129.94


⇒ 259.87 sq.cm


∴ Area of shaded region is 259.87 sq.cm


More from this chapter

All 27 →
2

Find the area of a circle inscribed in a square of side 28 cm. [Hint: Diameter of the circle is equal to the side of the square]

 3

Find the area of the shaded region in each of the following figures.


[Hint: d + +=42]


d = 21


∴ side of the square 21 cm

4

The adjacent figure consists of four small semi-circles of equal radii and two big semi-circles of equal radii (each 42 cm). Find the area of the shaded region.

 5

The adjacent figure consists of four half circles and two quarter circles. If OA = OB = OC = OD = 14 cm. Find the area of the shaded region.