document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1183227>Question 1183227</A>: <I><SPAN STYLE=\"word-break: break-all;\"> On his way home from the school board meeting, Kevin fills up his car. He likes the idea of using gasoline with ethanol but thinks his car can only handle 25% ethanol. At the gas station, he can use regular gas with 10% ethanol or E85 fuel with 85% ethanol.\r<BR>\n" );
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document.write( "How many gallons of each type of fuel should Kevin use if he wants to fill up his car with 10 gallons of fuel containing 25% ethanol?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #813452 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</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=813452\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Here is an alternative method for solving 2-part mixture problems like this, if a formal algebraic solution is not required.<br><BR>\n" );
document.write( "You are mixing 10% ethanol and 85% ethanol, and you want to get 25% ethanol.<BR>\n" );
document.write( "Look at the three percentages on a number line and observe/calculate that 25% is 1/5 of the way from 10% to 85%.  (10 to 85 is a difference of 75; 10 to 25 is a difference of 15; 15/75 = 1/5.)<BR>\n" );
document.write( "That means 1/5 of the mixture needs to be the higher percentage ingredient.<br><BR>\n" );
document.write( "ANSWER: 1/5 of 10 gallons, or 2 gallons, of the 85% ethanol; the other 8 gallons of 10% ethanol.<br><BR>\n" );
document.write( "CHECK:<BR>\n" );
document.write( ".85(2)+.10(8) = 1.7+.8 = 2.5<BR>\n" );
document.write( ".25(10) = 2.5<br><BR>\n" );
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