document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=242596>Question 242596</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A water tank has an inlet pipe and a drain pipe. <BR>\n" );
document.write( "A full tank can be emptied in 30 minutes if the drain is opened and an empty tank can be filled in 45 minutes with the inlet pipe opened.<BR>\n" );
document.write( " If both pipes are accidentally opened when the tank is full, then how long will it take to<BR>\n" );
document.write( "empty the tank?<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #177949 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=177949\">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" );
document.write( " A full tank can be emptied in 30 minutes if the drain is opened and an empty tank can be filled in 45 minutes with the inlet pipe opened. <BR>\n" );
document.write( "If both pipes are accidentally opened when the tank is full, then how long will it take to empty the tank?<BR>\n" );
document.write( ":<BR>\n" );
document.write( "let t = time (in minutes) to empty with both valves open<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let 1 = the completed job (an empty tank)<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Plus is draining, minus is filling<BR>\n" );
document.write( ":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2F30 ALIGN=MIDDLE  ALT=\"t%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2F45 ALIGN=MIDDLE  ALT=\"t%2F45\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "Multiply by 90, get rid of the denominators, results:<BR>\n" );
document.write( "3t - 2t = 90<BR>\n" );
document.write( "t = 90 minutes to empty with both valves open </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );