document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=433470>Question 433470</A>: <I><SPAN STYLE=\"word-break: break-all;\"> working together, two crews can clear snow from the city's streets in 20 hours.working alone the faster crew requires 9 hours less time than the slower crew. How many hours would it take each crew to clear the streets working alone? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #300483 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=300483\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> working together, two crews can clear snow from the city's streets in 20 hours.<BR>\n" );
document.write( "working alone the faster crew requires 9 hours less time than the slower crew.<BR>\n" );
document.write( " How many hours would it take each crew to clear the streets working alone?<BR>\n" );
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document.write( "x = time required by the faster crew<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(x+9) = time required by the slow pokes<BR>\n" );
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document.write( "Let the completed job = 1; (snow-free streets)<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2Fx ALIGN=MIDDLE  ALT=\"20%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2F%28%28x%2B9%29%29 ALIGN=MIDDLE  ALT=\"20%2F%28%28x%2B9%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "Multiply by x(x+9), results<BR>\n" );
document.write( "20(x+9) + 20x = x(x+9)<BR>\n" );
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document.write( "20x + 180 + 20x = x^2 + 9x<BR>\n" );
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document.write( "40x + 180 = x^2 + 9x<BR>\n" );
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document.write( "0 = x^2 + 9x - 40x - 180<BR>\n" );
document.write( "A quadratic equation<BR>\n" );
document.write( "x^2 - 31x - 180 = 0<BR>\n" );
document.write( "This will factor to<BR>\n" );
document.write( "(x-36)(x+5) = 0<BR>\n" );
document.write( "the positive solution<BR>\n" );
document.write( "x = 36 hrs required by the faster crew<BR>\n" );
document.write( "the<BR>\n" );
document.write( "36 + 9 = 45 hrs required by the slow pokes<BR>\n" );
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document.write( ":<BR>\n" );
document.write( "Check this<BR>\n" );
document.write( "20/36 + 20/45 = <BR>\n" );
document.write( ".56 + .44 = 1.0 </SPAN>\n" );
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