Discussion of Question with ID = 038 under Volume-and-Surface-Areas

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Question

What is the radius of a sphere if the ratio of volume to the surface area is 2 : 31?

A

${6/31}$ units.

B

$1{7/30}$ units.

C

$2{2/33}$ units.

D

3 units.

Soln.
Ans: a

Let R be the radius. Then $V/S = {4/3 × \text"π" × R^3}/{4 × \text"π" × R^2}$ = $R/3$, so R = 3 × ratio = ${6/31}$.


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