document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171063>Question 171063</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'm trying to work this problem and I think that it actually will be a linear equation, but I'm having problems trying to set it up to make it come out right.\r<BR>\n" );
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document.write( "  An auto service center has ten fifty-five gallon drums of 90% ethylene glycol, a common antifreeze fluid used in car radiators. The service center also has eight fifty-five gallon drums of 40% ethylene glycol solution as well. The manager wants to mix appropriate amounts of these two solutions to make 100 gallons of a 55% ethylene glycol concentration. How many gallons of the 90% solution will she need? \r<BR>\n" );
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document.write( "Can you help me with this one?  I'm studying to take my final exam this coming Friday and I believe there will be questions of this type on my final.\r<BR>\n" );
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document.write( "Thank you\r<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 #126296 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=126296\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The problem description contains a lot of extraneous data that will not be needed in solving this problem, so, beware of this on your test.<BR>\n" );
document.write( "You'll need to sort out the wheat from the chaff, as the saying goes.<BR>\n" );
document.write( "The fact that the Auto Center has  ten fifty-five gallon drums of 90% and eight fifty-five gallon drums of 40% ethylene glycol is interesting but not required to solve the problem. <BR>\n" );
document.write( "Let x = the number of gallons of 90% ethylene glycol solution needed ((90%)x).<BR>\n" );
document.write( "Then the manager will need to mix (100-x) gallons of the 40% ethylene glycol solution ((40%(100-x)) with that to get the 100 gallons of 55% ethylene glycol solution (55%(100)).<BR>\n" );
document.write( "After changing the percentages to their decimal equivalents: (90% = 0.9, 40% = 0.4, and 55% = 0.55), you can express this as follows:<BR>\n" );
document.write( "0.9x+0.4(100-x) = 0.55(100) Simplify and solve for x.<BR>\n" );
document.write( "0.9x+40-0.4x = 55 Combine like-terms.<BR>\n" );
document.write( "0.5x+40 = 55 Subtract 40 from both sides.<BR>\n" );
document.write( "0.5x = 15 Divide both sides by 0.5<BR>\n" );
document.write( "x = 30 gallons of 90% ethylene glycol solution.<BR>\n" );
document.write( "Suffice it to say that the manager has enough ethylene glycol solution on hand to do the job. </SPAN>\n" );
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