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Question
The radius of a circular garden is 100 m. There is a road 10 m wide, running all around it. Find the area of the road and the cost of levelling it at Rs 20 per m2. [Use π = 3.14]
Solution
Area of the road = Area of outer circle − Area of inner circle
= πR2 - πr2
= π [(110)2 - (100)2]
= 3.14 × 2100
= 6594 m2
Cost of levelling the road = Area of the road ⨯ Rate
= 6594 ⨯ 20
= Rs 131880
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