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Find the Surface Area of a Sphere of Radius 10.5 Cm . - Mathematics

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Question

Find the surface area of a sphere of radius 10.5 cm . 

Solution

Given radius = 10.5cm  
Surface area = `4πr^2`

= 4 × `22/7 × (10.5)^2`

= 1386 `cm^2`

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

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RD Sharma Mathematics [English] Class 9
Chapter 21 Surface Areas and Volume of a Sphere
Exercise 21.1 | Q 1.1 | Page 8

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