A dome of a building is in the form of a hemisphere. From inside, it was white-washed at the cost of Rs 498.96. If the cost of white-washing is Rs 2.00 per square meter, find the

(i) Inside surface area of the dome,


(ii) Volume of the air inside the dome

(i) Cost of white-washing the dome from inside = Rs 498.96

Cost of white-washing 1 m2 area = Rs 2


Therefore, CSA of the inner side of dome =


= 249.48 m2


(ii) Let the radius be r


CSA = 249.48 m2


2r2 = 249.48


2 * * r2 = 249.48


r = 6.3 m


Volume of air inside the dome = Volume of hemispherical dome


= πr3


= * * (6.3)3


= 523.908 m3


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