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प्रश्न
If the radius of a sphere is doubled, what is the ratio of the volume of the first sphere to that of the second sphere?
उत्तर
Let `V_1` and `V_2` be the volumes of first sphere and second sphere respectively
Radius of `1^"st"` sphere = r
`2^"nd"` sphere radius = 2r
∴ `(Volume 1^"st")/(volume 2^"nd")=(4/3πr^3)/(4/3π(2r)^3)=1/8`
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