document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=587628>Question 587628</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Jerry works 3 hours faster than David. Together they complete 5 jobs in 18 hours. How long does it take Jerry alone?\r<BR>\n" );
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document.write( "jerry = x<BR>\n" );
document.write( "dave = x+3\r<BR>\n" );
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document.write( "1/x * 18 + (1/x+3) * 18 = 5\r<BR>\n" );
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document.write( "I think....but it just doesn't work how I think it should. I appreciate your help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #374168 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=374168\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Jerry works 3 hours faster than David. Together they complete 5 jobs in 18 hours. How long does it take Jerry alone? <BR>\n" );
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document.write( "First, I will assume the work rates for David and Jerry are for one job.<BR>\n" );
document.write( "let x=hours for Jerry to complete one job alone<BR>\n" );
document.write( "5x=hours for Jerry to complete 5 jobs alone<BR>\n" );
document.write( "1/5x=work rate for Jerry to complete 5 jobs<BR>\n" );
document.write( "..<BR>\n" );
document.write( "(x+3) hours for David to complete one job alone<BR>\n" );
document.write( "5(x+3) hours for David to complete 5 jobs alone<BR>\n" );
document.write( "1/5(x+3)=work rate for David<BR>\n" );
document.write( "..<BR>\n" );
document.write( "It took18 hours to complete 5 jobs (100%)<BR>\n" );
document.write( "18/5x+18/5(x+3)=1<BR>\n" );
document.write( "LCD:5x*5(x+3)<BR>\n" );
document.write( "18*5(x+3)+18*5x=5x*5(x+3)<BR>\n" );
document.write( "90x+270+90x=25x^2+75x<BR>\n" );
document.write( "25x^2-105x-270=0<BR>\n" );
document.write( "divide by 5<BR>\n" );
document.write( "5x^2-21x-54=0<BR>\n" );
document.write( "(5x+9)(x-6)=0<BR>\n" );
document.write( "5x+9=0<BR>\n" );
document.write( "x=-9/5 (reject, x>0)<BR>\n" );
document.write( "x-6=0<BR>\n" );
document.write( "x=6<BR>\n" );
document.write( "Ans:<BR>\n" );
document.write( "hours for Jerry to complete one job alone=6 hrs<BR>\n" );
document.write( "hours for Jerry to complete 5 jobs alone=5x=30 hrs<BR>\n" );
document.write( "..<BR>\n" );
document.write( "Note:your set up correctly found the hours for Jerry to complete one job alone, but I see the problem better the way I set it up.  </SPAN>\n" );
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