Question 1037896
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A submarine can withstand 300 pounds per square inch of sea pressure before buckling.
If sea pressure increases by 40 pounds per square inch for every 100 feet of depth, how deep can the submarine go 
if it wants to maintain 20% margin of safety?
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20% margin of pressure gives you an admittable pressure of


300 - 300*0.2 = 260 pounds per square inch.


The determine the depth x (in feet) from the proportion

{{{x/100}}} = {{{260/40}}}.

x = {{{(260*100)/40}}}.


Please calculate it yourself.
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