document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=139700>Question 139700</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me:<BR>\n" );
document.write( "A boy walked over hills at 3 kilometers per hour and on flat roads at 4 kilometers per hour. He walked 18 kilometers in 5 hours. How much of his trip was over hills?<BR>\n" );
document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #101821 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=101821\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h ALIGN=MIDDLE  ALT=\"h\"   DISABLED_style= \"max-width:90%; height:auto;\" >= km walked on hills<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f ALIGN=MIDDLE  ALT=\"f\"   DISABLED_style= \"max-width:90%; height:auto;\" >= km walked on flat groun<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+%2B+f+=+18 ALIGN=MIDDLE  ALT=\"h+%2B+f+=+18\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%2F3+%2B+f%2F4+=+5 ALIGN=MIDDLE  ALT=\"h%2F3+%2B+f%2F4+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f+=+18+-+h ALIGN=MIDDLE  ALT=\"f+=+18+-+h\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Use substitution<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%2F3+%2B+%2818+-+h%29%2F4+=+5 ALIGN=MIDDLE  ALT=\"h%2F3+%2B+%2818+-+h%29%2F4+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply each side by 12<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4h+%2B+3%2A%2818+-+h%29+=+60 ALIGN=MIDDLE  ALT=\"4h+%2B+3%2A%2818+-+h%29+=+60\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4h+%2B+54+-+3h+=+60 ALIGN=MIDDLE  ALT=\"4h+%2B+54+-+3h+=+60\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h+=+6 ALIGN=MIDDLE  ALT=\"h+=+6\"   DISABLED_style= \"max-width:90%; height:auto;\" >km<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f+=+18+-+h ALIGN=MIDDLE  ALT=\"f+=+18+-+h\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f+=+18+-+6 ALIGN=MIDDLE  ALT=\"f+=+18+-+6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f+=+12 ALIGN=MIDDLE  ALT=\"f+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" >km<BR>\n" );
document.write( "6 km of the trip was over hills<BR>\n" );
document.write( "check answer:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h%2F3+%2B+f%2F4+=+5 ALIGN=MIDDLE  ALT=\"h%2F3+%2B+f%2F4+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F3+%2B+12%2F4+=+5 ALIGN=MIDDLE  ALT=\"6%2F3+%2B+12%2F4+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2+%2B+3+=+5 ALIGN=MIDDLE  ALT=\"2+%2B+3+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );