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The Surface Area of a Sphere is 5544 `Cm^2`, Find Its Diameter.

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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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Chapter 21: Surface Areas and Volume of a Sphere - Exercise 21.1 [Page 8]

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R.D. Sharma Mathematics [English] Class 9
Chapter 21 Surface Areas and Volume of a Sphere
Exercise 21.1 | Q 4 | Page 8

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