document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=412926>Question 412926</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A snowstorm causes a bus driver to decrease the usual average rate along a 60-mile route by 15 miles per hour. As a result, the bus takes two hours longer than usual to complete the route. At what average rate does the bus usually cover the 60-mile route?\r<BR>\n" );
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document.write( "My book says that the Answer is 30mph. I suspect the problem has to do with Time = Distance / Rate, but am unsure how to set up the problem properly. Please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #289935 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=289935\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let usual speed be x mph<BR>\n" );
document.write( "time with decreased speed - time with usual speed = 2\r<BR>\n" );
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document.write( "60/(x-15)  - 60/x =2\r<BR>\n" );
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document.write( "LCD = x(x-15)\r<BR>\n" );
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document.write( "multiply by the LCD<BR>\n" );
document.write( "60x-60(x-15)= 2x(x-15)<BR>\n" );
document.write( "60x-60x+900=2x^2-30x<BR>\n" );
document.write( "2x^2-30x-900=0<BR>\n" );
document.write( "/2<BR>\n" );
document.write( "x^2-15x-450=0<BR>\n" );
document.write( "x^2-30x+15x-450=0<BR>\n" );
document.write( "x(x-30)+15(x-30)=0<BR>\n" );
document.write( "(x-30)(x+15)=0<BR>\n" );
document.write( "x= 30 mph the original speed </SPAN>\n" );
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