Q29 of 40 Page 1

Following figure depicts a park where two opposite sides are parallel and left and right ends are semi-circular in shape. It has a 7m wide track for walking


Two friends Seema and Meena went to the park. Meena said that area of the track is 4066 m2. Is she right. Explain.


From the given figure, the track consists of 2 rectangular shaped sides and 2 semicircular shaped sides.


For the rectangular shaped side, length = 120 m and width = 7 m


For the semicircular shaped side, diameter = 70 – 2 × 7 = 70 – 14 = 56 m


So, radius of smaller semicircle = 28 m


Area of rectangular side = 120 × 7 = 840 m2


Area of semicircular side = Area of larger semicircle – Area of smaller semicircle =


Here, R = 28 + 7 = 35 m



= 11 × 5 × 35 – 11 × 4 × 28


= 693 m2


Therefore, area of track = 2 × 840 + 2× 693


= 1680 + 1386


= 3066 m2


Thus, Meena is not right as the area is 3066 m2.


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