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Question
Find the surface area of a sphere, if its volume is 38808 cubic cm. `(π = 22/7)`
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Solution
Let the radius of the sphere be r cm.
Volume of the sphere (V) = 38808 cm3
Volume of the sphere (V) = `4/3πr^3`
⇒ 38808 = `4/3 xx 22/7 xx r^3`
⇒ r3 = `[38808 xx21]/88` = 9261
⇒ r3 = 9261
⇒ r3 = `root3(9261)`
⇒ r = 21 cm
∴ Surface area of the sphere = 4πr2
= `4 xx 22/7 xx (21)^2`
= 5544 cm2
Thus, the surface area of the sphere is 5544 cm2.
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