A hemi-spherical dome of a building needs to be painted. IF the circumference of the base of the dome is 17.6 m, find the cost of painting it, given the cost of painting is Rs. 5 per 100 cm^{2}.

Circumference of a circle = 2πr

Surface area of a hemisphere = 2πr^{2}

Given, base of the dome is 17.16 m

⇒ 2 × (22/7) × r = 17.6

⇒ r = 2.8 m

Surface area of the hemisphere = 2 × (22/7) × 2.8^{2} = 49.28 m^{2} = 492800 cm^{2}

Cost of painting is Rs. 5 per 100 cm^{2},

Cost of painting the dome = (492800/100) × 5 = Rs. 24640

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