document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=745578>Question 745578</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An inlet pipe can fill an artificial pond in 60 minutes, while an outlet pipe can empty it in 80 minutes. If both pipes are left on, how long will it take the pond to fill?\r<BR>\n" );
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document.write( "Can you help me set this up and solve please  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #453923 by </B><A HREF=/tutors/aboutme.mpl?userid=savvyhush23><B>savvyhush23(50)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=savvyhush23><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=savvyhush23><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=453923\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An inlet pipe can fill an artificial pond in 60 minutes, while an outlet pipe can empty it in 80 minutes. If both pipes are left on, how long will it take the pond to fill?\r<BR>\n" );
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document.write( "Let i - rate of inlet pipe and o - rate of outlet pipe\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=i=1%2F60 ALIGN=MIDDLE  ALT=\"i=1%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=o=-1%2F80 ALIGN=MIDDLE  ALT=\"o=-1%2F80\"   DISABLED_style= \"max-width:90%; height:auto;\" > (negative (-) since it is draining the pond)<BR>\n" );
document.write( "...both pipes are left on, so together their rate is: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=i+%2B+o+=+%281%2F60%29%2B%28-1%2F80%29=1%2F240 ALIGN=MIDDLE  ALT=\"i+%2B+o+=+%281%2F60%29%2B%28-1%2F80%29=1%2F240\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The pond must be fill, so it is 1 complete work.<BR>\n" );
document.write( "Formula for work: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=work=rate%2Atime ALIGN=MIDDLE  ALT=\"work=rate%2Atime\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So, the time to fill the tank is, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=time=work%2Frate ALIGN=MIDDLE  ALT=\"time=work%2Frate\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=time=1%2F%281%2F240%29=240 ALIGN=MIDDLE  ALT=\"time=1%2F%281%2F240%29=240\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "answer: 240 minutes </SPAN>\n" );
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