document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=201658>Question 201658</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780073533490/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Filling a tank. 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 #151905 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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/cgi-bin/show-face.mpl?user=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=151905\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Garamond\" size=\"+2\">\r<BR>\n" );
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document.write( "By itself, the drain can empty <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \frac{1}{30}\"> of the tank in 1 minute.  By itself, the inlet can fill <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \frac{1}{45}\"> of the tank in 1 minute.\r<BR>\n" );
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document.write( "Since filling takes longer than emptying, the net effect is that the tank will empty itself, so with both valves open,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \frac{1}{30} - \frac{1}{45}\">\r<BR>\n" );
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document.write( "of the tank will empty in one minute, and it will then take\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \frac{1}{\frac{1}{30} - \frac{1}{45}}\">\r<BR>\n" );
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document.write( "minutes for the tank to empty.  You get to do the arithmetic.  Hint: LCD = 90.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi} + 1 = 0\"><BR>\n" );
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