document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=630582>Question 630582</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Christopher traveled by motorcycle at an average speed of 54 miles per hour.\r<BR>\n" );
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document.write( "Then, he traveled by train at an average speed of 31 miles per hour.\r<BR>\n" );
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document.write( "In total, he traveled 165 miles for 5 hours.\r<BR>\n" );
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document.write( "How many miles did Christopher travel by train? (Round to the nearest mile.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #397034 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=397034\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Christopher traveled by motorcycle at an average speed of 54 miles per hour. <BR>\n" );
document.write( "Then, he traveled by train at an average speed of 31 miles per hour. <BR>\n" );
document.write( "In total, he traveled 165 miles for 5 hours. <BR>\n" );
document.write( "How many miles did Christopher travel by train? (Round to the nearest mile.)<BR>\n" );
document.write( "**<BR>\n" );
document.write( "let x=miles traveled by train<BR>\n" );
document.write( "165-x=miles traveled by motorcycle<BR>\n" );
document.write( "travel time=distance/speed<BR>\n" );
document.write( "..<BR>\n" );
document.write( "54/(165-x)+31/x=5<BR>\n" );
document.write( "LCD:x(165-x)<BR>\n" );
document.write( "54x+31(165-x)=5x(165-x)<BR>\n" );
document.write( "54x+5115-31x=825x-5x^2<BR>\n" );
document.write( "5x^2-802x+5115=0<BR>\n" );
document.write( "solve by following quadratic formula:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "a=5, b=-802, c-5115<BR>\n" );
document.write( "ans:<BR>\n" );
document.write( "x&#8776;6.6538<BR>\n" );
document.write( "miles traveled by train=7\r<BR>\n" );
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document.write( " </SPAN>\n" );
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