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Find the total surface area of a hemisphere of radius 10 cm. [Use π = 3.14]

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Question

Find the total surface area of a hemisphere of radius 10 cm. [Use π = 3.14]

Sum
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Solution

Radius (r) of hemisphere = 10 cm

Total surface area of hemisphere = Curved surface area of a hemisphere + Area of circular end of hemisphere

= 2πr2 + πr2

= 3πr2

= [3 × 3.14 × (10)2] cm2

= 942 cm2

Therefore, the total surface area of such a hemisphere is 942 cm2.

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Chapter 11: Surface Area and Volumes - EXERCISE 11.2 [Page 145]

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NCERT Mathematics [English] Class 9
Chapter 11 Surface Area and Volumes
EXERCISE 11.2 | Q 3. | Page 145

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