document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=746010>Question 746010</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In one week, Fearless Frank drove 100 miles on the freeway and 150 miles in town. His car consumed 18.2 gallons of gasoline. The next week his journeys took him over 180 miles of freeway and 30 miles of local driving, and he used only 10.9 gallons of gas. What were his highway m.p.g. and his local m.p.g.?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #454105 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=454105\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The key is to see that ( miles driven ) / ( miles / gallon ) = gallons<BR>\n" );
document.write( "I can say:<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+ ALIGN=MIDDLE  ALT=\"+a+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = mpg on the highway<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+ ALIGN=MIDDLE  ALT=\"+b+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = mpg in town<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+100+%2F+a+%2B+150+%2F+b+=+18.2+ ALIGN=MIDDLE  ALT=\"+100+%2F+a+%2B+150+%2F+b+=+18.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+%2F+a+%2B+30+%2F+b+=+10.9+ ALIGN=MIDDLE  ALT=\"+180+%2F+a+%2B+30+%2F+b+=+10.9+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1000+%2F+a+%2B+1500+%2F+b+=+182+ ALIGN=MIDDLE  ALT=\"+1000+%2F+a+%2B+1500+%2F+b+=+182+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1800+%2F+a+%2B+300+%2F+b+=+109+ ALIGN=MIDDLE  ALT=\"+1800+%2F+a+%2B+300+%2F+b+=+109+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "Multiply both sides of (2) by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5+ ALIGN=MIDDLE  ALT=\"+5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and subtract (1) from (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+9000+%2F+a+%2B+1500+%2F+b+=+545+ ALIGN=MIDDLE  ALT=\"+9000+%2F+a+%2B+1500+%2F+b+=+545+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-1000+%2F+a+-+1500+%2F+b+=+-182+ ALIGN=MIDDLE  ALT=\"+-1000+%2F+a+-+1500+%2F+b+=+-182+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+8000%2A%281%2Fa%29+=+363+ ALIGN=MIDDLE  ALT=\"+8000%2A%281%2Fa%29+=+363+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+8000+%2F+363+ ALIGN=MIDDLE  ALT=\"+a+=+8000+%2F+363+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+22.039+ ALIGN=MIDDLE  ALT=\"+a+=+22.039+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1800+%2F+22.039+%2B+300+%2F+b+=+109+ ALIGN=MIDDLE  ALT=\"+1800+%2F+22.039+%2B+300+%2F+b+=+109+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+81.673+%2B+300%2Fb+=+109+ ALIGN=MIDDLE  ALT=\"+81.673+%2B+300%2Fb+=+109+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+300%2Fb+=+27.327+ ALIGN=MIDDLE  ALT=\"+300%2Fb+=+27.327+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+300+%2F+27.327+ ALIGN=MIDDLE  ALT=\"+b+=+300+%2F+27.327+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+10.978+ ALIGN=MIDDLE  ALT=\"+b+=+10.978+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "His highway m.p.g. was about 22<BR>\n" );
document.write( "and his local m.p.g. was about 11<BR>\n" );
document.write( "-----------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+100+%2F+22.039+%2B+150+%2F+10.978+=+18.2+ ALIGN=MIDDLE  ALT=\"+100+%2F+22.039+%2B+150+%2F+10.978+=+18.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4.537+%2B+13.664+=+18.2+ ALIGN=MIDDLE  ALT=\"+4.537+%2B+13.664+=+18.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+18.2007+=+18.2+ ALIGN=MIDDLE  ALT=\"+18.2007+=+18.2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "close enough\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );