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Question
Find the surface area of a sphere of radius 10.5 cm.
`["Assume "pi=22/7]`
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Solution
Radius (r) of sphere = 10.5 cm
Surface area of sphere = 4πr2
= `[4xx22/7xx(10.5)^2] cm^2`
= `(4xx22/7xx10.5xx10.5) cm^2`
= (88 × 1.5 × 10.5) cm2
= 1386 cm2
Therefore, the surface area of a sphere having a radius of 10.5 cm is 1386 cm2.
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