document.write( "Question 253212: A water tank has an inlet pipe and a drain pipe. A full tank can be emptied in 30 minutes if the drain is opened and empty tank can be filled in 45 minutess with the inlet pipe opened. If both pipes are accidently opened when the tank is full, then how long would it take to empty the tank?\r
\n" ); document.write( "\n" ); document.write( "I believe this is a trick question and can possible be unknown. \n" ); document.write( "
Algebra.Com's Answer #185449 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
This is a job / time question. Here are the things we need:
\n" ); document.write( "J1 = job of inlet pipe
\n" ); document.write( "J2 = job of drain pipe
\n" ); document.write( "T1 = time of inlet pipe
\n" ); document.write( "T1 = time of drain pipe
\n" ); document.write( "x = time together
\n" ); document.write( "Tj = total number of tanks.
\n" ); document.write( "--
\n" ); document.write( "The basic formula is
\n" ); document.write( "(i) (J1/T1)*(x) + (J2/T1)*(x) = Tj
\n" ); document.write( "--
\n" ); document.write( "From this we can fill in some information:
\n" ); document.write( "-(1/30)*(x) + (1/45)*(x) = 1.
\n" ); document.write( "--
\n" ); document.write( "Solving, we get:
\n" ); document.write( "-3x + 2x = 90, which means x = -90
\n" ); document.write( "Since x will be negative, there is no solution based on the information given. If the 30 and 45 were reversed, then we would get an answer. \n" ); document.write( "
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