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Find the radius of a sphere whose surface area is 154 cm2. Assume [Assume π=227] - Mathematics

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प्रश्न

Find the radius of a sphere whose surface area is 154 cm2.

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

 

योग
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उत्तर

Let the radius of the sphere be r.

Surface area of sphere = 154

∴ 4πr= 154 cm2

r2 = `((154xx7)/(4xx22))cm^2`

= `((7xx7)/(2xx2))cm^2`

r = `(7/2) cm` = 3.5 cm

Therefore, the radius of the sphere whose surface area is 154 cm2 is 3.5 cm.

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अध्याय 13: Surface Area and Volumes - Exercise 13.4 [पृष्ठ २२५]

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एनसीईआरटी Mathematics [English] Class 9
अध्याय 13 Surface Area and Volumes
Exercise 13.4 | Q 6 | पृष्ठ २२५

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