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Find the Total Surface Area of a Hemisphere and a Solid Hemisphere Each of Radius 10 Cm. (Use ๐œ‹ = 3.14)

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Question

Find the total surface area of a hemisphere and a solid hemisphere each of radius 10 cm.
(Use ๐œ‹ = 3.14)

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Solution

The surface area of the hemisphere =  `2πr^2` 

- `2 × 3.14 × (10)^2`

- `628 cm^2`

The surface area of solid hemisphere  =` 3πr^2`

- `3 × 3.14 × (10)^2`

-`942 cm^2`

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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 3 | Page 8

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