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Question
Find the cost of polishing a circular table-top of diameter 1.6 m, if the rate of polishing is ₹ 15/m2. (Take π = 3.14)
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Solution
Diameter = 1.6 m
Radius = `1.6/2`
= 0.8 m
Area = πr2
= 3.14 × 0.8 × 0.8
= 2.0096 m2
Cost for polishing 1 m2 area = ₹ 15
Cost for polishing 2.0096 m2 area
= 15 × 2.0096
= 30.14
Therefore, it will cost ₹ 30.14 for polishing such circular table.
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