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Question
The surface area of a sphere is 2464 cm2. If its radius be doubled, then what will be the surface area of the new sphere?
Solution
Let the radii of the given sphere and the new sphere be r and R, respectively.
We have,
R = 2r and the surface area of the given sphere = 24 cm2
`i.e. 4pir^2 = 2464 cm2`
The surface area of the given sphere = 2464 cm2
`i.e 4pir^2 = 2426` cm2
The surface area of the new sphere = 4πR2
`= 4pi (2r)^2`
`= 4pi (4r)^2`
`= 4 (4pir^2)`
`= 4xx2464`
`= 9856 cm^2`
So, the surface area of the new sphere is 9856 cm2.
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