मराठी

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

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प्रश्न

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

 
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उत्तर

In the given problem, we have to find the radius of a sphere whose surface area is given.

Surface area of the sphere (S) = 154 cm2

Let the radius of the sphere be cm

Now, we know that surface area of the sphere =  `4pi r^2`

So,

`154=4(22/7)(r)^2`

`r^2 = ((154)(7))/((4)(22))`

`r^2 = 12.25`

Further, solving for r

`r = sqrt(12.25)`

r = 3.5

Therefore, the radius of the given sphere is 3.5 cm .

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पाठ 21: Surface Areas and Volume of a Sphere - Exercise 21.3 [पृष्ठ २५]

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आर.डी. शर्मा Mathematics [English] Class 9
पाठ 21 Surface Areas and Volume of a Sphere
Exercise 21.3 | Q 3 | पृष्ठ २५

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