document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=325750>Question 325750</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 40% antifreeze solution is to be mixed with a 70% solution to get 90 L of a 50% solution. How many liters of the 40% and 70% solutions will be needed?\r<BR>\n" );
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document.write( "I must solve this problem using a system of equations.\r<BR>\n" );
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document.write( "my first equation is x + y = 90, am I on the right track? what would the second equation be? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #233191 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=233191\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A 40% antifreeze solution is to be mixed with a 70% solution to get 90 L of a 50% solution. How many liters of the 40% and 70% solutions will be needed? <BR>\n" );
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document.write( "Quantity Equation: x + y = 90 L<BR>\n" );
document.write( "Alcohol Equation:0.4x+0.7y = 0.5*90<BR>\n" );
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document.write( "Multiply thru 1st by 4<BR>\n" );
document.write( "Multiply thru 2nd by 10<BR>\n" );
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document.write( "4x + 4y = 4*90<BR>\n" );
document.write( "4x + 7y = 5*90<BR>\n" );
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document.write( "Subtract 1st from 2nd and solve for \"y\":<BR>\n" );
document.write( "3y = 90<BR>\n" );
document.write( "y = 30 L (amt of 70% antifreeze needed in the mixture)<BR>\n" );
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document.write( "Since x + y = 90, x = 60 L (amt of 40% antifreeze needed in the mixture)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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