The surface areas of two sphere are in the ratio of 4:25. Find the ratio of their volumes.


Let suppose the radius of first spheres = r


And the radius of second spheres = R


As per the question,


Surface area of the first sphere /Surface area of the second sphere = 4/25


4πr2/4πR2 = 4/25


(r/R)2 = 4/25


r/R = √4/25


r/R = 2/5 …………………(i)


Now,




= (r/R)3


= (2/5)3 …………………[Using (i)]


= 8/125


= 8 : 125


So,


The ratio of the volumes of the given spheres will be 8 : 125


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