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Question
Find the radius of a sphere whose surface area is 154 cm2.
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Solution
In the given problem, we have to find the radius of a sphere whose surface area is given.
Surface area of the sphere (S) = 154 cm2
Let the radius of the sphere be r cm
Now, we know that surface area of the sphere = `4pi r^2`
So,
`154=4(22/7)(r)^2`
`r^2 = ((154)(7))/((4)(22))`
`r^2 = 12.25`
Further, solving for r
`r = sqrt(12.25)`
r = 3.5
Therefore, the radius of the given sphere is 3.5 cm .
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