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Find the surface area of a sphere of diameter 3.5 m. Assume [Assume π=227] - Mathematics

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प्रश्न

Find the surface area of a sphere of diameter 3.5 m.

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

योग

उत्तर

Radius (r) of sphere = `"Diameter"/2`

= `3.5/2`

= 1.75 m

Surface area of sphere = 4πr2

= `[4 xx 22/7 xx (1.75)^2] m^2`

= 38.5 m2

Therefore, the surface area of the sphere having diameter 3.5 m is 38.5 m2.

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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 2.3 | पृष्ठ २२५

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