Question 181308
A column of water 2.31 feet high exerts a pressure of one (1) pound per square inch. How much pressure does a column of water 46.20 feet high exert? 
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Each 2.31 ft exerts 1 psi.  So 4.62 feet would be 2 psi.
psi = feet of column/2.31
psi = 46.2/2.31 = 20
46.2' exerts 20 psi
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The pressure, in psi, is the depth (in feet) divided by 2.31.