A hemispherical dome of a building needs to be painted. If the circumference of the base of the
Come is 17.6 m, find the cost of painting it, given the cost of painting is 5 per 100 cm".

Respuesta :

Answer:

The cost of painting the hemispherical dome is 110880 unit  

Step-by-step explanation:

Given as for a hemispherical dome :

The circumference of base = 17.6 m

The cost of painting it = 5 unit per 100 cm²

∵ circumference of base = circumference of circle = 2×[tex]\pi[/tex]×radius

So ,17.6 m = 2×[tex]\pi[/tex]×radius

Or, Radius = [tex]\frac{17.6\times 7}{2\times 22}[/tex]

Or, Radius = [tex]\frac{123.2}{44}[/tex] = 2.8 m

Or, R = 280 cm

So, Total surface area of hemispherical dome = 3×[tex]\pi[/tex]×radius²

or, Total surface area of hemispherical dome = 3×[tex]\pi[/tex]×280²

Or, Total surface area of hemispherical dome = [tex]\frac{3\times 22\times 280\times 280}{7}[/tex]

Or, Total surface area of hemispherical dome = [tex]\frac{5174400}{7}[/tex]

Total surface area of hemispherical dome = 739200 cm²

Now, The cost of painting 100 cm² is 15 unit

So,   The cost of painting 739200 cm² = [tex]\frac{15\times 739200}{100}[/tex]

Or, The cost of painting 739200 cm² = 110880 unit

Hence The cost of painting the hemispherical dome is 110880 unit  Answer