From a rectangular sheet of paper ABCD wit AB = cm and AD = 28 cm, a semicircular portion wit BC as diameter is cut off. Find the area of the remaining paper.

Given:

Length of rectangular sheet of paper = 40 cm


Breadth of rectangular sheet of paper = 28 cm


Radius of the semicircular cut out = 14 cm


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Area of rectangle = length × breadth


Area of rectangular sheet of paper = 40 × 28


= 1120 cm2


Area of semicircle = πr2


Area of semicircular cut out = × × 14 × 14


= 22 × 14 = 308 cm2


Thus, the area of remaining sheet of paper = Area of rectangular sheet of paper – Area of semicircular cut out


= 1120 – 308 = 812 cm2


Hence, the area of remaining sheet of paper is 812 cm2.


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