document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=715261>Question 715261</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A pool can be filled by one pipe in 7 hours and by a second pipe in 9 hours. How long will it take using both pipes to fill the pool </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #439330 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=439330\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"Fill the pool\" is 1 job.\r<BR>\n" );
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document.write( "Pipe_____________rate______________time_______________jobs<BR>\n" );
document.write( "Pipe One_________(____)____________7__________________1<BR>\n" );
document.write( "Pipe Two_________(____)____________9__________________1<BR>\n" );
document.write( "Both Pipes_______(_____)__________(___)_______________1\r<BR>\n" );
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document.write( "Fill in the missing information.  r*t=j, meaning r=j/t.\r<BR>\n" );
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document.write( "Pipe_____________rate______________time_______________jobs<BR>\n" );
document.write( "Pipe One_________(1/7)____________7__________________1<BR>\n" );
document.write( "Pipe Two_________(1/9)____________9__________________1<BR>\n" );
document.write( "Both Pipes_______(1/7+1/9)__________(___)_______________1\r<BR>\n" );
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document.write( "RATE means how many jobs per hour.  The combined rate of both pipes together only needs to be computed from the sum.\r<BR>\n" );
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document.write( "Combined Rate, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F7%2B1%2F9=%289%2B7%29%2F63 ALIGN=MIDDLE  ALT=\"1%2F7%2B1%2F9=%289%2B7%29%2F63\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%2816%2F63%29 ALIGN=MIDDLE  ALT=\"highlight%2816%2F63%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > JOBS PER HOUR.\r<BR>\n" );
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document.write( "What the question asks is how many hours to do the job which is to \"fill the pool.\"  We just need the reciprocal of this combined rate. That is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%2863%2F16%29 ALIGN=MIDDLE  ALT=\"highlight%2863%2F16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > hours. </SPAN>\n" );
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