Q27 of 35 Page 311

Three circular plate were cut off from a tin plate with equal width if the ratio of length of diameter of three circles is 3:5:7, let us see by calculating the ratio of their weight.

Given ratio of diameter of three circles =3:5:7



⇒ Ratio of their radius = 3:5:7


∵ Area of a circle = πr2


⇒ Ratio of their areas = 3× 3 : 5× 5 : 7× 7


⇒ Ratio of their areas = 9 : 25 : 49


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