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Assuming the Earth to Be a Sphere of Radius 6370 Km, How Many Square Kilo Metres is Area of the Land, If Three-fourth of the Earth’S Surface is Covered by Water? - Mathematics

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Question

Assuming the earth to be a sphere of radius 6370 km, how many square kilo metres is area
of the land, if three-fourth of the earth’s surface is covered by water?

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Solution

`3^(th) /4`of earth surface is covered by water

∴ `1^(th)/4` earth surface is covered by land

 ∴  Surface area covered by land `- 1/4 × 4πr^2`

`- 1/4 × 4 ×  22/7× 6370^2`

- `127527.4km^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 7 | Page 8

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