document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=713049>Question 713049</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Pump A can fill a swimming pool in 30 hours, while working together with pump B they will fill the pool in 12 hours. How much time would it take pump B 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 #438263 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=438263\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> One job is filling the pool.  Rate as gallons per hours.<BR>\n" );
document.write( "Rate*Time=Jobs\r<BR>\n" );
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document.write( "Pump__________rate__________time_____________jobs<BR>\n" );
document.write( "A_____________1/30_____________30____________1<BR>\n" );
document.write( "B______________r______________(<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" >)____________1<BR>\n" );
document.write( "A & B__________1/12______________12_____________1\r<BR>\n" );
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document.write( "While A and B work together, each pump contributes its own rate to the sum of the simultaneous rates.  \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%281%2F30%2Br=1%2F12%29 ALIGN=MIDDLE  ALT=\"highlight%281%2F30%2Br=1%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, find r, which is units of jobs per hour.  Note that the question is asking how many hours to fill the pool by pump B alone, which means how many hours per 1 job.  This is the RECIPROCAL of r.  We essentially are looking for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" > in the above table.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=1%2F12-1%2F30 ALIGN=MIDDLE  ALT=\"r=1%2F12-1%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=%285-2%29%2F30 ALIGN=MIDDLE  ALT=\"r=%285-2%29%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=3%2F30 ALIGN=MIDDLE  ALT=\"r=3%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28r=1%2F10%29 ALIGN=MIDDLE  ALT=\"highlight%28r=1%2F10%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Answer:  That means 10 hours for pump B to fill the pool </SPAN>\n" );
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