document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=51789>Question 51789</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 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 65% ethylene glycol concentration. How many gallons of the 90% solution will she need?\r<BR>\n" );
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document.write( "a. 10<BR>\n" );
document.write( "b. 20<BR>\n" );
document.write( "c. 30<BR>\n" );
document.write( "d. 40<BR>\n" );
document.write( "e. 50<BR>\n" );
document.write( "f. 60<BR>\n" );
document.write( "g. 70<BR>\n" );
document.write( "h. 80<BR>\n" );
document.write( "i. 90<BR>\n" );
document.write( "j. none of these </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #34561 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=34561\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 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 65% ethylene glycol concentration. How many gallons of the 90% solution will she need? <BR>\n" );
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document.write( "90% Fluid DATA:<BR>\n" );
document.write( "Let amount of 90% fluid be \"x\"<BR>\n" );
document.write( "Amount of active ingredient is 0.90x gallons.<BR>\n" );
document.write( "40% Fluid DATA:<BR>\n" );
document.write( "Amount of 40% fluid is \"100-x\" gallons.<BR>\n" );
document.write( "Amount of active ingredient is 0.40(100-x)= 40-0.4x<BR>\n" );
document.write( "Mixed Fluid DATA:<BR>\n" );
document.write( "Amount is 100 gallons.<BR>\n" );
document.write( "Amount of active ingredient is 0.65(100)= 65 gallons<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "active + active = active<BR>\n" );
document.write( "0.90x + 40-0.4x = 65<BR>\n" );
document.write( "Multiply thru by 100 to get:<BR>\n" );
document.write( "90x + 4000-40x=6500<BR>\n" );
document.write( "50x = 1500<BR>\n" );
document.write( "x=30 gallons of 90% fluid<BR>\n" );
document.write( "100-x=70 gallons of 40% fluid<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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