document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1102648>Question 1102648</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How much 78 octane gas and 91 octane gas should be blended to make 13 gallons of 87 octane gas? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #717347 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=717347\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "I will hope you get other responses from other tutors showing the classic method for solving \"mixture\" problems like this.  I use a different method which is much faster and easier.<br><BR>\n" );
document.write( "Think of three numbers on a number line: the 78 and 91 octane of the two fuels being mixed, and the 87 octane of the mixture.<br><BR>\n" );
document.write( "The 87 is 9/13 of the way from 78 to 91.  (91-78 = 13; 87-78 = 9)<br><BR>\n" );
document.write( "That means 9/13 of the mixture must be the 91 octane, with the rest being the 78 octane.<br><BR>\n" );
document.write( "The amount of the mixture is 13 gallons; 9/13 of 13 gallons is 9 gallons.<br><BR>\n" );
document.write( "You need to mix 9 gallons of the 91 octane with 4 gallons of the 78 octane to get 13 gallons of 87 octane. </SPAN>\n" );
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