document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=182103>Question 182103</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A water tank has an inlet pipe and a drain<BR>\n" );
document.write( "pipe. A full tank can be emptied in 30 minutes if the drain<BR>\n" );
document.write( "is opened and an empty tank can be filled in 45 minutes<BR>\n" );
document.write( "with the inlet pipe opened. If both pipes are accidentally<BR>\n" );
document.write( "opened when the tank is full, then how long will it take to<BR>\n" );
document.write( "empty the tank? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #136677 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=136677\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A water tank has an inlet pipe and a drain pipe.<BR>\n" );
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document.write( "A full tank can be emptied in 30 minutes if the drain<BR>\n" );
document.write( "is opened and an empty tank can be filled in 45 minutes<BR>\n" );
document.write( "with the inlet pipe opened. <BR>\n" );
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document.write( "If both pipes are accidentally opened when the tank is full, <BR>\n" );
document.write( "then how long will it take to empty the tank?<BR>\n" );
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document.write( "Drain pipe DATA:<BR>\n" );
document.write( "time = 30 min/job ; rate = (1/30) job/min<BR>\n" );
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document.write( "Fill pipe DATA:<BR>\n" );
document.write( "time = 45 min/job ; rate = 1/45 job/min<BR>\n" );
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document.write( "Together DATA:<BR>\n" );
document.write( "time = x min/job ; rate = 1/x job/min<BR>\n" );
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document.write( "Equations:<BR>\n" );
document.write( "fill rate - drain rate = together emptying rate<BR>\n" );
document.write( "1/30 - 1/45 = 1/x\r<BR>\n" );
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document.write( "45x-30x 30*45<BR>\n" );
document.write( "15x = 30*45<BR>\n" );
document.write( "x = 90 min (time to empty the tank when both pipes are open<BR>\n" );
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document.write( "Chers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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