Find the area of the shaded field shown in figure.



We can clearly see that the figure comprises of a rectangle and a semi-circle.



Name the rectangle ABCD. Name the point where the


rectangle and the semi-circle meets as E.


Take any point F on the semi-circle, then we have


the semi-circle as EFD.


Now, area of the figure = Area of the semi-circle + Area of the rectangle.


Here, from the figure, Radius of the semi-circle = r = 6 - 4 = 2 m


Area of the semi-circle = πr2/2 = 4π/2 = 2π


Also, area of the rectangle = Length × Breadth


= AB × BC


= 4 × 8 = 32 m2


Area of shaded region = Area of rectangle ABCD + Area of semi-circle DEF


= (32 +2π) m2


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