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Question
The surface area of a sphere is 616 sq cm. Find its radius tan β = `3/4`
Solution
Given, surface area of sphere = 616 cm2
We know that,
Surface area of sphere = 4πr2
∴ 4πr2 = 616
⇒ r2 = `616/(4π)`
⇒ r2 = `(616 xx 7)/(4 xx 22)`
⇒ r2 = 49
⇒ r = 7 cm
Hence, radius of sphere is 7 cm.
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