document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1032872>Question 1032872</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Heater A warms a room from 40 degrees to 70 degrees in 5 hours. Heater B can do this job in 7 hours. Heater A alone is started but breaks down in 2.5 hours. How long will it take heater B to finish the job. \r<BR>\n" );
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document.write( "* a chart would be especially helpful*  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #647460 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39630)</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=647460\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The exercise is intended as a uniform rates problem, each \"worker\" being a heater, working at its own rate.  You can make a chart or table of rates.\r<BR>\n" );
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document.write( "One job is \"warm the room air from 40 to 70 degree\".\r<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">HEATER          RATE\r\n" );
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document.write( "A               1/5\r\n" );
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document.write( "B               1/7</PRE>\r<BR>\n" );
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document.write( "Another chart may be what you want, but the rest of the solution will be through equations only.  The rule to use will be  RT=J relating rate, time, job.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28%281%2F5%29%282.5%29%2B%281%2F7%29x=1%29 ALIGN=MIDDLE  ALT=\"highlight_green%28%281%2F5%29%282.5%29%2B%281%2F7%29x=1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > for the heaters working separately, to do ONE JOB.  The unknown time for heater B to work to finish the job is x.\r<BR>\n" );
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document.write( "Once that is understood, solving for unknown time x is uncomplicated arithmetic. </SPAN>\n" );
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