Q6 of 36 Page 249

The length of a side of a square field is 20 m. A cow is tied at the corner by means of a 6 m long rope. Find the area of the field which the cow can graze. Also find the increase in the grazing area, if length of the rope is increased by 2 m. (π = 3.14)

length of side of a square field (a) = 20 m


length of the rope (r1) = 6 m



since it is square the center angle (θ) = 90o


area of the gazing field =


=


= 28.26 m2


If the length of rope is increased by 2m


The radius of the gazing field (r2) = 6m + 2m = 8m


area of the gazing field =


=


= 50.24 m2


increase in gazing field = 50.24 – 28.26


= 27.98 m2


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