Q5 of 48 Page 13

If the height of a sphere and a cube is the same. Find the ratio of their total surface areas.

Concept Used: Total Surface Area of Sphere = 4 π r2


Total Surface Area of Cube = a3


Where r = radius of the sphere and a = edge of the cube.


Given:


The height of the sphere and cube are same.


Explanation:


Height of Sphere = The diameter of Sphere = 2 r


Where, r = radius of the sphere


And let the edge of the cube = ‘a’ cm


From the question we get,


2 r = a



The ratio of Surface Areas




The ratio of Surface Areas


Hence, The ratio of their total surface areas


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