a well of diameter 3 m is dug 14 m deep . the earth taken out of it has beem spread evenly all around of it in the shape of circular ring of width 4 m to form embankment. find the height of embankment .
volume of earth is π*(3/2)^2 * 14 = 63π/2 m^3
The area of the ring is π(4 + 3/2)^2 - (3/2)^2) = 28π m^2
So, the thickness of the ring is
(63π/2 m^3) ÷ (28π m^2) = 9/8 m