document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=866734>Question 866734</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One roofing crew can finish a 2,800-square-foot roof in 12 hours, and another crew can do the job in 10 hours. If they work together, can they finish before a predict rain in 5 hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #522447 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=522447\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The rates of each crew are:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F12 ALIGN=MIDDLE  ALT=\"1%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F10 ALIGN=MIDDLE  ALT=\"1%2F10\"   DISABLED_style= \"max-width:90%; height:auto;\" > JOBS per HOUR.\r<BR>\n" );
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document.write( "The way uniform rates situations go, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=R%2Ax=y ALIGN=MIDDLE  ALT=\"R%2Ax=y\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  In the kind of application for your example, x is time in hours and y is how much or many jobs.  The unit of R is jobs per hour and R is a rate.  The rate of each crew working together is the sum of their individual rates, so:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F12%2B1%2F10=10%2F120%2B12%2F120=%2810%2B12%29%2F120=22%2F120=highlight%2811%2F60%29 ALIGN=MIDDLE  ALT=\"1%2F12%2B1%2F10=10%2F120%2B12%2F120=%2810%2B12%29%2F120=22%2F120=highlight%2811%2F60%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > jobs per hour.\r<BR>\n" );
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document.write( "Now, if rain will come in 5 hours, will this 5 hours be enough time to do ONE complete 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%2811%2F60%29%2A5%3E=1%29 ALIGN=MIDDLE  ALT=\"highlight_green%28%2811%2F60%29%2A5%3E=1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  ?   Is this true or false?\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=55%2F60%3E=1 ALIGN=MIDDLE  ALT=\"55%2F60%3E=1\"   DISABLED_style= \"max-width:90%; height:auto;\" > FALSE.<BR>\n" );
document.write( "The two crews together will not be able to finish the roof before the rain prediction time. </SPAN>\n" );
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