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प्रश्न
Find the radius of a sphere whose surface area is 154 cm2.
`["Assume "pi=22/7]`
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उत्तर
Let the radius of the sphere be r.
Surface area of sphere = 154
∴ 4πr2 = 154 cm2
r2 = `((154xx7)/(4xx22))cm^2`
= `((7xx7)/(2xx2))cm^2`
r = `(7/2) cm` = 3.5 cm
Therefore, the radius of the sphere whose surface area is 154 cm2 is 3.5 cm.
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