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 #208478 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=208478\">put this solution on YOUR website!</A><BR><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<BR>\n" );
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document.write( "Experienced rate = 1/26 roof/hr<BR>\n" );
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document.write( "Beginner rate = 1/39 roof/hr<BR>\n" );
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document.write( "Together rate = 1/x roof/hr<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "rate + rate = together rate<BR>\n" );
document.write( "1/26 + 1/39 = 1/x<BR>\n" );
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document.write( "Multiply thru by 26*39x to get:<BR>\n" );
document.write( "39x + 26x = 26*39<BR>\n" );
document.write( "65x = 26*39<BR>\n" );
document.write( "x = 78/5 = 15.6 hrs. (time to finish the roof if they work together)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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