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Find the surface area of a sphere of radius 5.6 cm. Assume [Assume π=227]

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Question

Find the surface area of a sphere of radius 5.6 cm.

`["Assume "pi=22/7]`

Sum
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Solution

Radius(r) of sphere = 5.6 cm

Surface area of sphere = 4πr2

`=[4xx22/7xx(5.6)^2]cm^2`

= (88 × 0.8 × 5.6) cm2

= 394.24 cm2

Therefore, the surface area of a sphere having radius 5.6 cm is 394.24 cm2.

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Chapter 11: Surface Area and Volumes - EXERCISE 11.2 [Page 144]

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NCERT Mathematics [English] Class 9
Chapter 11 Surface Area and Volumes
EXERCISE 11.2 | Q 1. (ii) | Page 144

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