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Question
The surface area of a sphere is 5544 `cm^2`, find its diameter.
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Solution
Surface area of a sphere is 5544cm^2`
⇒`4πr^2 - 5544`
⇒`(4×22)/7 × r^2 -5544`
⇒`r^2 - (5544 × 7)/88`
⇒ r - `sqrt(21 cm × 21 cm) - sqrt ((21)^2 cm) `
⇒ r - 21 cm
Diameter = 2 (radius )
-2 (21cm)
- 42 cm .
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