document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189846>Question 1189846</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A chemical company makes two brands of antifreeze. The first brand is 70% pure antifreeze, and the second brand is 95% pure antifreeze. In order to obtain 50<BR>\n" );
document.write( "gallons of a mixture that contains 75% pure antifreeze, how many gallons of each brand of antifreeze must be used? \r<BR>\n" );
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document.write( "First brand ? Gallons <BR>\n" );
document.write( "Second brand ? Gallons  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #821336 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=821336\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x = the amount of solution in the first brand.<BR>\n" );
document.write( "let y = the amount of solution in the second brand.\r<BR>\n" );
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document.write( "you have two equations that need to be solved simultaneously.<BR>\n" );
document.write( "they are:\r<BR>\n" );
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document.write( "x + y = 50<BR>\n" );
document.write( ".7 * x + .95 * y = .75 * 50\r<BR>\n" );
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document.write( "multiply both sides of the first equation by .7 and lease the second equation as is to get:<BR>\n" );
document.write( ".7 * x + .7 * y = .7 * 50<BR>\n" );
document.write( ".7 * x + .95 * y = .75 * 50\r<BR>\n" );
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document.write( "simplify the right side of each equation to get:<BR>\n" );
document.write( ".7 * x + .7 * y = 35<BR>\n" );
document.write( ".7 * x + .95 * y = 37.5\r<BR>\n" );
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document.write( "subtract the first equation from the second to get:<BR>\n" );
document.write( ".25 * y = 2.5\r<BR>\n" );
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document.write( "solve for y to get:<BR>\n" );
document.write( "y = 10\r<BR>\n" );
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document.write( "that means x = 40 because 40 + 10 = 50\r<BR>\n" );
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document.write( "confirm the solution is correct by replacing x with 40 and y with 10 in both original equations.\r<BR>\n" );
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document.write( "x + y = 50 becomes 40 + 10 = 50 which becomes 50 = 50<BR>\n" );
document.write( ".7 * x + .95 * y becomes .7 * 40 + .95 * 10 which becomes 28 + 9.5 which becomes 37.5\r<BR>\n" );
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document.write( "this confirms the solution is correct.<BR>\n" );
document.write( "the solution is 40 gallons of the first brand and 10 gallons of the second brand is required.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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