document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=93781>Question 93781</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone please help me out with this equation please?<BR>\n" );
document.write( " A dr office mixed a 75% disinfectant solution with a 25% disinfectant solution. How many liters of each were used to make 20L of a 40% disinfectant solution. Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #68323 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=68323\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Let x=number of liters of 75% solution\r<BR>\n" );
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document.write( "Then 20-x=number of liters of 25% soluton\r<BR>\n" );
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document.write( "Now we know that the amount of pure disinfectant in the 75% solution (0.75x) plus the amount of pure disinfectant in the 25% solution(0.25(20-x)) must equal the amount of pure disinfectant in the final mixture (0.40(20)).  So our equation to solve is:\r<BR>\n" );
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document.write( "0.75x+0.25(20-x)=0.40*20  get rid of parens\r<BR>\n" );
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document.write( "0.75x+5-0.25x=8  subtract 5 from both sides\r<BR>\n" );
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document.write( "0.75x+5-5-0.25x=8-5  collect like terms\r<BR>\n" );
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document.write( "0.50x=3  divide both sides by 0.50\r<BR>\n" );
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document.write( "x=6 liters -------------------------amount of 75% solution needed\r<BR>\n" );
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document.write( "20-x=20-6=14 liters---------------------amount of 25% solution needed\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "6*0.75+14*0.25=20*0.40<BR>\n" );
document.write( "4.5+3.5=8<BR>\n" );
document.write( "8=8\r<BR>\n" );
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document.write( "Hope this helps---------------------ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
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