document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=735653>Question 735653</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A car travels 400 miles in 7 hours. Before noon the driver averages 60 miles per hour, but after noon he averages only 50 miles per hour. At what time did he leave? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #449513 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=449513\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A car travels 400 miles in 7 hours. Before noon the driver averages 60 miles per hour, but after noon he averages only 50 miles per hour. At what time did he leave?<BR>\n" );
document.write( "***<BR>\n" );
document.write( "let x=distance traveled before noon<BR>\n" );
document.write( "400-x=distance traveled after noon<BR>\n" );
document.write( "Travel time=distance/speed<BR>\n" );
document.write( "..<BR>\n" );
document.write( "travel time before noon plus travel time after noon=7 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2F60%2B%28400-x%29%2F50=7 ALIGN=MIDDLE  ALT=\"x%2F60%2B%28400-x%29%2F50=7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "50x+24000-60x=7*50*60<BR>\n" );
document.write( "-10x+24000=21000<BR>\n" );
document.write( "10x=3000<BR>\n" );
document.write( "x=300<BR>\n" );
document.write( "travel time before noon=x/60=300/60=5 hrs<BR>\n" );
document.write( "At what time did he leave? 5 hrs before noon=7 am </SPAN>\n" );
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