A well with 42 m inside diameter is dug 14 m deep. Soil taken out of it has been evenly spread all around it to a width of 21 m to form an embankment. Find the height of the embankment.

Volume of the soil dug out = πr²h ⟹(22/7x21 x 21 x 14) = 19,404 m³. Area of embankment = Area of embankment with well - Area of well = (22/7 x 42 x 42) - (22/7 x 21 x 21) = 4,714 m² Height of embankment = Volume/Area = 19404/4158 = 4.6 m (approx.)

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