SOLUTION: A well having diameter 3m was dug 14m deep.The earth taken out from it has been evenliy spread all around in to make enbankment os width 4m.find the height of enbankment. (ans

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Question 814602: A well having diameter 3m was dug 14m deep.The earth taken out from it has been evenliy spread all around in to make enbankment os width 4m.find the height of enbankment.

(answer:1.125m)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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A well having diameter 3m was dug 14m deep.
The earth taken out from it has been evenly spread all around in to make embankment of width 4m.
find the height of embankment.
:
The volume of the dirt removed from a well is a cylinder shape, the formula
V = pi%2Ar%5E2%2Ah
therefore (the radius is half the diameter)
V = pi%2A1.5%5E2%2A14
V = 99 cu/meters of dirt
:
Assuming it is to be spread around the well. (like a flattened doughnut)
Find the area of the whole thing minus the well. Radius, 1.5+4 = 5.5 m
A = pi%2A5.5%5E2 = pi%2A1.5%5E2
A = 95 - 7
A = 88 sq/m area of the dirt around the well
:
Divide the vol of the dirt, by the area of the dirt to get the height
99%2F88 = 1.125 meters high, 4 meters wide, is the embankment