How many cubic meters of earth must be dug out to make a well 28 m deep and 2.8 m in diameter ? Also, find the cost of plastering its inner surface at ₹ 4.50 per sq meter.
Mensuration
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How many cubic meters of earth must be dug out to make a well 28 m deep and 2.8 m in diameter ? Also, find the cost of plastering its inner surface at ₹ 4.50 per sq meter.

KnowledgeBoat · Accepted Answer

Given, Diameter of well = 2.8 m Radius of the well = = 1.4 m Depth of the well = 28 m. Volume of earth dug out = Volume of well = πr²h = x 1.4 x 1.4 x 28 = 172.48 m³. Area of curved surface = 2πrh = 2 x x 1.4 x 28 = 2 x 22 x 0.2 x 28 = 246.4 m². Given, the cost of plastering at the rate of ₹ 4.50 per sq meter. ∴ Cost of plastering inner surface = ₹ 246.40 x 4.50 = ₹ 1108.80. Hence, volume of earth to be dug out = 172.48 m³ and cost of plastering inner surface = ₹ 1108.80.

Mathematics

How many cubic meters of earth must be dug out to make a well 28 m deep and 2.8 m in diameter ? Also, find the cost of plastering its inner surface at ₹ 4.50 per sq meter.

Mensuration

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How many cubic meters of earth must be dug out to make a well 28 m deep and 2.8 m in diameter ? Also, find the cost of plastering its inner surface at ₹ 4.50 per sq meter.

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