In the given figure, a square OABC is inscribed in a quadrant OPBQ of a circle. IF OA = 20 cm, find the area of the shaded region. [Use π = 3.14]


Given:

OA = Side of square OABC = 20 cm


Area of square = Side × Side


Area of square OABC = 20 × 20 = 400 cm2


Now,


Length of diagonal of square = √2 × Side of Square


Length of diagonal of square OABC = √2 × 20 = 20√2 cm


Radius of the quadrant = 20√2 cm


Area of quadrant = πr2


Area of quadrant OPBQ = × 3.14 × 20√2 × 20√2


= × 400 × 2


= 3.14 × 200 = 628 cm2


Area of shaded region = Area of quadrant OPBQ – Area of square OABC = 628 – 400 = 228 cm2


Hence, the area of the shaded region is 228 cm2.


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