Math, asked by RagingEmber, 10 months ago

an electric lamp in the form of a glass hemispherical base surmounted by a metallic cylindrical top of same radius 21 cm and height 3.5cm.the top was silver coated and the glass surface was painted red 
1) what is the cost of silver coating the top at the rate of RS 5 per 100 cm²?

Answers

Answered by Rebeccareji
0

surface area to be painted red = 2772cm2

Step-by-step explanation:

Area to be coated with silver = 2πrh+πr2=πr(2h+r)

=22/7×21(7+21)

=66×28

=1848cm²

Cost of silver coating=1848/100 × 5

=92.5Rs

Surface area to be painted red = 2πr²

=2×22/7×21×21

=2772cm²

Answered by arvindbhaiasalaliya
0

Answer:

4.5

Step-by-step explanation:

please branlist answer

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