document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=818894>Question 818894</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A homeowner estimates that it will take her 7 days to roof her house. A professional roofer estimates that he could roof the house in 2 days. How long will it take if the home owner helps the roofer? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #492853 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=492853\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Each of them might work according to his stated, given work speed.  The work speeds are additive.\r<BR>\n" );
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document.write( "Use the speeds (rates) in the form of roofs per day.<BR>\n" );
document.write( "Homeowner rate plus roofer rate equals their combined rate:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F7%29%2B%281%2F2%29=2%2F14%2B7%2F14=highlight%289%2F14%29 ALIGN=MIDDLE  ALT=\"%281%2F7%29%2B%281%2F2%29=2%2F14%2B7%2F14=highlight%289%2F14%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > roofs per day, like 9 roofs in 14 days.\r<BR>\n" );
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document.write( "You are interested in the reciprocal, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14%2F9=highlight%281%265%2F9%29 ALIGN=MIDDLE  ALT=\"14%2F9=highlight%281%265%2F9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > day for 1 roof.<BR>\n" );
document.write( "A more realistic interpretation requires a little more information about how many hours per day is given for any day's work.   </SPAN>\n" );
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