In the given figure, ABCD is a square of side 4 cm. A quadrant of a circle of radius 1 cm is also drawn. Find the area of the shaded region.
(CBSE 2012)
Given:
Side of the square = 4 cm
Radius of the quadrants at the corners = 1 cm
Radius of the circle in the centre = 1 cm
∵ 4 quadrants = 1 circle
∴ There are 2 circles of radius 1 cm
Area of square = side × side
= 4 × 4 = 16 cm2
Area of 2 circles = 2 × πr2
= 2 × × 1 × 1 =
cm2
∵ Area of shaded region = Area of square – Area of 2 circles
= 16 -
= =
cm2 = 9.7 cm2
Hence, the area of shaded region is 9.72 cm2.