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Question
Find the surface area of a sphere of diameter 14 cm.
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Solution
The diameter = 14 cm.
∴ radius (r) = 7 cm.
The surface area of a sphere = 4πr2
= `4 xx 22/7 xx (7)^2`
= `4 xx 22/7 xx 7 xx 7`
= 88 × 7
= 616
The surface area of the sphere is 616 cm2.
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(Use π = `22/7`)
