document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=864058>Question 864058</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I did a problem very similar to this one and I got it wrong. I really need help and I have to show all of my work!\r<BR>\n" );
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document.write( "On a 1287 mile long trip in windy conditions, a family calculates their fuel economy to be 18 miles per gallon over the 2 days it takes to reach their destination. On their 2-day return trip, with similar wind at their backs, their calculations show a fuel economy of 26 miles per gallon.\r<BR>\n" );
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document.write( "#1 Calculate the expected fuel economy of their vehicle in ideal (non-windy) conditions (f) as well as the influence of the wind (w) in miles per gallons.\r<BR>\n" );
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document.write( "#2Compare how many gallons of fuel they used for the round trip to the expected usage in idea (non-windy) travel conditions. Which uses more? By how many gallons? Round to the nearest hundredth, if necessary?\r<BR>\n" );
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document.write( "Thnaks for any help!!!!!!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #520809 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=520809\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Uniform rates problem, fuel efficiency.<BR>\n" );
document.write( "Rv=d for Rate volume distance; distance in miles, volume in gallons.\r<BR>\n" );
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document.write( "__________________Rate__________volume__________distance<BR>\n" );
document.write( "Going_____________18____________x_______________18x=1287<BR>\n" );
document.write( "Returning_________26____________y_______________26y=1287\r<BR>\n" );
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document.write( "The volumes x and y can be easily calculated.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1287%2F18=highlight%2871.5%29 ALIGN=MIDDLE  ALT=\"x=1287%2F18=highlight%2871.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > gallons, GOING;<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=1287%2F26=highlight%2849.5%29 ALIGN=MIDDLE  ALT=\"y=1287%2F26=highlight%2849.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > gallons, RETURNING.\r<BR>\n" );
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document.write( "To look at the rates for wind-effect and fuel efficiency without the wind, try assigning variables r and w.  <BR>\n" );
document.write( "r = fuel efficiency without wind<BR>\n" );
document.write( "w = the influence of the wind<BR>\n" );
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document.write( "______________Rate___________volume___________distance<BR>\n" );
document.write( "GOING_________r-w____________71.5_____________1287<BR>\n" );
document.write( "RETURN________r+w____________49.5_____________1287\r<BR>\n" );
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document.write( "This arrangement gives also two equations in the two unknowns, now r and w.<BR>\n" );
document.write( "This system:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r-w%2971.5=1287 ALIGN=MIDDLE  ALT=\"%28r-w%2971.5=1287\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r%2Bw%2949.5=1287 ALIGN=MIDDLE  ALT=\"%28r%2Bw%2949.5=1287\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "The volumes were already found from x and y in the previous part of the problem.<BR>\n" );
document.write( "The rest of the work for r and w are for you to finish. </SPAN>\n" );
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