document.write( "Question 993052: pipe A can fill the tank alone in 5 hrs amd pipe B can fill the tank in 4 hours.A drain pipe (pipe c) can empty the tank in 20hrs/ with all three pipes open, how long it will take to fill the tank? \n" ); document.write( "
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pipe A can fill the tank alone in 5 hrs amd pipe B can fill the tank in 4 hours.A drain pipe (pipe c) can empty the tank in 20hrs/ with all three pipes open, how long it will take to fill the tank?
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\n" ); document.write( "Each hour:
\n" ); document.write( "Pipe A adds 1/5 of a tank
\n" ); document.write( "Pipe B adds 1/4 of a tank
\n" ); document.write( "Pipe C subtracts 1/20 of a tank
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\n" ); document.write( "Can you finish it?
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