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A Hemispherical Bowl Made of Brass Has Inner Diameter 10.5 Cm. Find the Cost of Tin- Plating It on the Inside at the Rate of Rs. 4 per 100 `Cm^2` - Mathematics

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Question

A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of tin- plating
it on the inside at the rate of Rs. 4 per 100 `cm^2`

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Solution

Given
Inner diameter of hemisphere bowl -10.5cm

Radius -  `(10.5)/2`cm - 5.25 cm . 

Surface area of hemispherical bowl - 2πr 

- 2`[22/7] × (5.25)^2 cm ^2`

-` 173 .25 cm^2`

Cost of tin planning 100`cm^2` area = Rs. 4

Cost of tin planning `173.25 cm^2` area = Rs .`((4 xx173.25)/100)`

= Rs. 6.93 

Thus, The cost of tin plating the inner side of hemisphere bowl is Rs .6 93 

 

 

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Chapter 21: Surface Areas and Volume of a Sphere - Exercise 21.1 [Page 8]

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RD Sharma Mathematics [English] Class 9
Chapter 21 Surface Areas and Volume of a Sphere
Exercise 21.1 | Q 5 | Page 8

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