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Find the volume of a sphere, if its surface area is 154 sq.cm.

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प्रश्न

Find the volume of a sphere, if its surface area is 154 sq.cm.

योग
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उत्तर

Let the radius of the sphere be r cm.

Surface area of the sphere = 154 cm2

∴ 4πr2 = 154 cm2

⇒ `4 xx 22/7 xx r^2` = 154

⇒ r2 = `[154 xx 7]/88`

⇒ r2 = 12.25

⇒ r2 = (3. 5)2

⇒ r = 3. 5

∴ Volume of the sphere = `4/3 πr^3`

= `4/3 xx 22/7 xx (3. 5)^3`

= 179.67 cm3

Thus, the volume of the sphere is 179.67 cm3.

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अध्याय 9: Surface Area and Volume - Problem Set 9 [पृष्ठ १२३]

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बालभारती Mathematics 2 [English] Standard 9 Maharashtra State Board
अध्याय 9 Surface Area and Volume
Problem Set 9 | Q 6. | पृष्ठ १२३

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