document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=287709>Question 287709</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An experienced roofer can roof a house in 26 hours. A beginning roofer needs 39 hours to complete the same job. Find how long it takes for the two of them to do the job together.\r<BR>\n" );
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document.write( "This is what i know:<BR>\n" );
document.write( "I think I need to use direct or inverse variation equations\r<BR>\n" );
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document.write( "This is what I've tried:<BR>\n" );
document.write( "y=k/x <BR>\n" );
document.write( "26=k/39--Multiple by 39 to get k by itself<BR>\n" );
document.write( "1014=k\r<BR>\n" );
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document.write( "The back of my textbook says the answer is 15.6 hours\r<BR>\n" );
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document.write( "Thank you for your time.<BR>\n" );
document.write( "This homework is due tomorrow.<BR>\n" );
document.write( "I'm grateful for any help I can get<BR>\n" );
document.write( "Thanks again </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #208474 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=208474\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An experienced roofer can roof a house in 26 hours.<BR>\n" );
document.write( " A beginning roofer needs 39 hours to complete the same job.<BR>\n" );
document.write( " Find how long it takes for the two of them to do the job together.<BR>\n" );
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document.write( "Here is how I would do it:<BR>\n" );
document.write( "let t = time required for them to complete the job together<BR>\n" );
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document.write( "let 1 = the completed job<BR>\n" );
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document.write( "Each does a fraction of the job, the two fractions add up to 1<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2F26 ALIGN=MIDDLE  ALT=\"t%2F26\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2F39 ALIGN=MIDDLE  ALT=\"t%2F39\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply equation by 1014 (that's 26*39), results<BR>\n" );
document.write( "39t + 26t = 1014<BR>\n" );
document.write( "65t = 1014<BR>\n" );
document.write( "t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1014%2F65 ALIGN=MIDDLE  ALT=\"1014%2F65\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = 15.6 hrs<BR>\n" );
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document.write( "Check solution by find the faction that each does<BR>\n" );
document.write( "15.6/26 + 15.6/39 = <BR>\n" );
document.write( ".6 + .4 = 1 </SPAN>\n" );
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