document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1111708>Question 1111708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A family has two cars. The first car has a fuel efficiency of 15 miles per gallon of gas and the second has a fuel efficiency of 35 miles per gallon of gas. During one particular week, the two cars went a combined total of 825 miles, for a total gas consumption of 35 gallons. How many gallons were consumed by each of the two cars that week? \r<BR>\n" );
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document.write( "First car: ______ gallons <BR>\n" );
document.write( "Second car: ______ gallons  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #726733 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=726733\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The algebraic solutions shown by the other tutors are of course fine.  If you don't need to use algebra, there is an easy way to solve a problem like this using basic arithmetic and a bit of logical reasoning.<br><BR>\n" );
document.write( "Here is how you could solve this problem that way.<br><BR>\n" );
document.write( "If all 35 gallons of gas were used by the car that gets only 15 miles per gallon, the total number of miles would be 35*15 = 525 -- 300 miles short of the actual 825 miles.<BR>\n" );
document.write( "The more efficient car gets 20 more miles per gallon than the other.  To get 300 \"extra\" miles with the 35 gallons of gas, the number of gallons used by the more efficient car must be 300/20 = 15.<BR>\n" );
document.write( "That means the gas guzzler used 35-15=20 gallons.<br><BR>\n" );
document.write( "CHECK: 20*15 + 15*35 = 300+525 = 825 </SPAN>\n" );
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