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A sphere and a cube are of the same height. The ratio of their volumes is

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Question

A sphere and a cube are of the same height. The ratio of their volumes is 

Options

  • 3 : 4

  •  21 : 11

  • 4 : 3

  • 11 : 21

MCQ
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Solution

In the given problem, we have a sphere and a cube of equal heights. So, let the diameter of the sphere and side of the cube be x units.

So, volume of the sphere (V1) = `4/3 pi (d/2)^3`

`=4/3 pi (x/2)^3`

`=4/3 pi (x^3 /8)`

`= (pi x^3)/6`

Volume of the cube (V2) = S3

= x3

So, to find the ratio of the volumes,

`V_1/V-2 = (pi x^3/6)/x^3`

            ` = pi /6` 

           ` = ((22/7))/6`

           `=11/21 `

Therefore, the ratio of the volumes of sphere and cube of equal heights is  11 : 21. 

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Chapter 21: Surface Areas and Volume of a Sphere - Exercise 21.4 [Page 25]

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R.D. Sharma Mathematics [English] Class 9
Chapter 21 Surface Areas and Volume of a Sphere
Exercise 21.4 | Q 4 | Page 25

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