document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=720636>Question 720636</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A car travels a distance of 9000 KM with a certain average speed. If after travelling half the distance the average speed of the car be increased by 15 Km/Hrs., the time required to travel 900 Km, is reduces by 11/2 hour, find the original average speed of the car. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #441913 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=441913\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "Time = distance /speed\r<BR>\n" );
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document.write( "original speed = x\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=450%2Fx+%2B450%2F%28x%2B15%29=+%28900%2Fx%29-+3%2F2 ALIGN=MIDDLE  ALT=\"450%2Fx+%2B450%2F%28x%2B15%29=+%28900%2Fx%29-+3%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=450%2F%28x%2B15%29-450%2Fx+=-3%2F2 ALIGN=MIDDLE  ALT=\"450%2F%28x%2B15%29-450%2Fx+=-3%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "450x-450(x+15) = (-3/2) ( x*(x+15)\r<BR>\n" );
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document.write( "-6750=(-3/2)(x^2+15x)\r<BR>\n" );
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document.write( "-13000=-3x^2-45x\r<BR>\n" );
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document.write( "3x^2+45x-13500=0\r<BR>\n" );
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document.write( "/3\r<BR>\n" );
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document.write( "x^2+15x-4500=0\r<BR>\n" );
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document.write( "x^2+75x-60-4500-0\r<BR>\n" );
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document.write( "(x+75)(x-60)=0\r<BR>\n" );
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document.write( "x= 60 km/h the original speed<BR>\n" );
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