हिंदी

A solid rectangular block of metal 49 cm by 44 cm by 18 cm is melted and formed into a solid sphere. Calculate the radius of the sphere.

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प्रश्न

A solid rectangular block of metal 49 cm by 44 cm by 18 cm is melted and formed into a solid sphere. Calculate the radius of the sphere.

योग
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उत्तर

Volume of rectangular block = 49 × 44 × 18 cm3

= 38808 cm3  ...(1)

Let r be the radius of sphere 

∴ Volume = `4/3pir^3`

= `4/3 xx 22/7 xx r^3`

= `88/21 r^3`  ...(2) 

From (1) and (2)  

`88/21 r^3 = 38808` 

`=> r^3 = 38808 xx 21/88 = 441 xx 21` 

`=>` r3 = 9261 

`=>` r = 21 cm 

Radius of sphere = 21 cm

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अध्याय 20: Cylinder, Cone and Sphere - Exercise 20 (D) [पृष्ठ ३०८]

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सेलिना Concise Mathematics [English] Class 10 ICSE
अध्याय 20 Cylinder, Cone and Sphere
Exercise 20 (D) | Q 5. | पृष्ठ ३०८

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