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Question
The dome of a building is in the form of a hemisphere. Its radius is 63 dm. Find the cost of
painting it at the rate of Rs. 2 per sq. m.
Solution
Dome Radius - 63d m - 6.3m
Inner S.A of dome - `2πr^2 - 2 × 22/7 × (6.3)^2 - 249.48 m^2`
Now . cost of `1m^2` = Rs. 2.
∴ Cost of `249.48m^2`- Rs [2 × 249.48]
- Rs.498.96.
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