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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) - Mathematics

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प्रश्न

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)

बेरीज
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उत्तर

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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पाठ 11: Perimeter and Area - Exercise 11.3 [पृष्ठ २२३]

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एनसीईआरटी Mathematics [English] Class 7
पाठ 11 Perimeter and Area
Exercise 11.3 | Q 8 | पृष्ठ २२३

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