Question

Q. A well is dug whose diameter is 4mand the depth is 10m. Find the quantity of the earth taken out. Calculate the cost of plastering the curved(inner) surface at Rs. 5.00 per square meter.

Answer 1

Answer:

Step-by-step explanation:

Ans.

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Diameter=4m

Radius=d/2=4/2=2m

Depth=10m

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Volume of earth taken out=πr²h=22/7×2×2×10=8800/7 m³

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Curved surface area=2πrh=2×22/7×2×10=8800/ 7m²=88000000/7 cm²

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Cost of plastering inner curved surface area:-

For 1 cm²=Rs. 5

For 88000000/7 cm²=62857142.8 rupees.

Answer 2

Answer:

Step-by-step explanation:

Diameter=4m

Radius=d/2=4/2=2m

Depth=10m

Volume of earth taken out =πr²h=22/7×2×2×10=8800/7 m³

Curved surface area

=2πrh=2×22/7×2×10=8800/ 7m²

=88000000/7 cm²

Cost of plastering inner curved surface area:-

For 1 cm²=Rs. 5

For 88000000/7 cm²=62857142.8 rupees.