document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=783856>Question 783856</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A family has two cars. During one particular week, the first car consumed 30 gallons of gas and the second consumed 35 gallons of gas. The two cars drove a combined total of 1450 miles, and the sum of their fuel efficiencies was 45  miles per gallon. What were the fuel efficiencies of each of the cars that week?\r<BR>\n" );
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document.write( "I am having trouble setting this up. Could you please help me?<BR>\n" );
document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #476943 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10552)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=476943\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "A family has two cars. During one particular week, the first car consumed 30 gallons of gas and the second consumed 35 gallons of gas. The two cars drove a combined total of 1450 miles, and the sum of their fuel efficiencies was 45  miles per gallon. What were the fuel efficiencies of each of the cars that week?\r<BR>\n" );
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document.write( "I am having trouble setting this up. Could you please help me?<BR>\n" );
document.write( "Thank you.\r<BR>\n" );
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document.write( "Let fuel efficiency for car 1 and car 2 be F, and S, respectively<BR>\n" );
document.write( "Then F + S = 45 ------- S = 45 – F ------ eq (i)<BR>\n" );
document.write( "Also, 30F + 35S = 1,450 ------ eq (ii)<BR>\n" );
document.write( "30F + 35(45 – F) = 1,450 ---------- Substituting 45 – F for S in eq (ii)<BR>\n" );
document.write( "30F + 1,575 – 35F = 1,450<BR>\n" );
document.write( "30F - 35F = 1,450 – 1,575 <BR>\n" );
document.write( "– 5F = - 125\r<BR>\n" );
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document.write( "F, or fuel efficency for car 1 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-+125%29%2F-+5 ALIGN=MIDDLE  ALT=\"%28-+125%29%2F-+5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%2825%29 ALIGN=MIDDLE  ALT=\"highlight_green%2825%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > miles per gallon\r<BR>\n" );
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document.write( "S = 45 – 25 ------- Substituting 25 for F in eq (i)<BR>\n" );
document.write( "S, or fuel efficiency for car 2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%2820%29 ALIGN=MIDDLE  ALT=\"highlight_green%2820%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > miles per gallon\r<BR>\n" );
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document.write( "You can do the check!! \r<BR>\n" );
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document.write( "Further help is available, online or in-person, for a fee, obviously. Send comments, “thank-yous,” and inquiries to “D” at MathMadEzy@aol.com </SPAN>\n" );
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