document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=781310>Question 781310</A>: <I><SPAN STYLE=\"word-break: break-all;\"> (Time required to do a job) Two pumps are available for filling a gasoline storage tank.  Pump A, used alone, can fill the tank in 3 hours, and pump B, used alone, can fill it in 4 hours.  If both pumps are used simultaneously, how long will it take to fill 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 #475857 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=475857\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The sum of their rates is the filling rate when both pumps work at the same time.\r<BR>\n" );
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document.write( "Pump A, 1/3 tanks per hour<BR>\n" );
document.write( "Pump B, 1/4 tanks per hour\r<BR>\n" );
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document.write( "Pump A and B Together, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F3%29%2B%281%2F4%29 ALIGN=MIDDLE  ALT=\"%281%2F3%29%2B%281%2F4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > tanks per hour<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F12%2B3%2F12 ALIGN=MIDDLE  ALT=\"4%2F12%2B3%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F12 ALIGN=MIDDLE  ALT=\"7%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" > tanks per hour.\r<BR>\n" );
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document.write( "The other way to describe this combined rate is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2F7=highlight%281%265%2F7%29 ALIGN=MIDDLE  ALT=\"12%2F7=highlight%281%265%2F7%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > HOURS to fill THE TANK. </SPAN>\n" );
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