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प्रश्न
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.
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उत्तर
Dome Radius − 63 dm − 6.3m
Inner S.A of dome = `2πr^2 − 2 × 22/7 × (6.3)^2 − 249.48 m^2`
Now, the cost of `1m^2` = Rs. 2.
∴ Cost of `249.48m^2` − Rs [2 × 249.48]
= Rs. 498.96.
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