The dome of the building where people live is in the shape of hemisphere of radius 7 m . Eleven children decided to help the old age people by collecting money for white washing the dome . If white washing cost ₹2per sq m . How much would each children pay ? Also find the volume of air inside the dome . What values are depicted here

Answer :

Given radius of hemisphere shaped building  =  7 m
And
We want to paint that building , So , we paint only its curved surface area .
And
We know Curved surface area of hemisphere  = 2 π r2
So,
Curved surface area of hemispherical building  = 2 ×227×7×7 = 2 × 22 × 7  = 308 m2
And rate of white wash is Rs 2 / m2 , So
Cost of painting the building  =  308 × 2  =  Rs. 616
And

There are eleven children who are collect that money , So

Total money paid by each children  = 61611Rs . 56                               ( Ans )
And
We know Volume of hemisphere  = 2 π r33
So,
Volume of hemispherical building  =  2×227× 7 × 7×  73 = 2 × 22 × 7×  73 = 21563 =  718.67 m3          ( Ans )

By doing show they depicts their helping nature towards old people .

  • 11
r = 7m

Surface area of hemisphere is 3* pi * r2
                                                   =3*22/7*7*7
                                                   = 462m2
Cost of white washing area of 1 sqm=Rs 2
Cost of white washing area of 462 sq.m= Rs 2*462
                                                                   = Rs 924

Money each child has to pay= Total money / Total students
                                                 = 924 / 11=Rs 84

Volume of hemisphere = 2 /3 * pi *r3
                                         =2 /3 *22/7 *7*7*7
                                         =718m3
Value depicted is care and respect for elders
I hope this will help you
 
   
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