document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=27140>Question 27140</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Chas has some 12% acid solution and some 32% acid solution. Determine how much<BR>\n" );
document.write( "of each he needs in order to get 40ml of a 20% acid solution.\r<BR>\n" );
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document.write( "I tried setting up the problem like this: .12(x)+ .32(x)=.2(40) but i didn't<BR>\n" );
document.write( "get the answer right </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #14748 by </B><A HREF=/tutors/aboutme.mpl?userid=AnlytcPhil><B>AnlytcPhil(1806)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=AnlytcPhil><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=AnlytcPhil><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=14748\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Chas has some 12% acid solution and some 32% acid solution. Determine how much<BR>\n" );
document.write( "of each he needs in order to get 40ml of a 20% acid solution. <BR>\n" );
document.write( "I tried setting up the problem like this: .12(x)+ .32(x)=.2(40) but i didn't<BR>\n" );
document.write( "get the answer right.<BR>\n" );
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document.write( "Your mistake is in letting the same letter x represent two different<BR>\n" );
document.write( "quantities.  You must let x represent only one of the quantities, and then<BR>\n" );
document.write( "either y or 40-x will represent the other.  Never let the same letter <BR>\n" );
document.write( "represent two different quantities in the same problem. There are four ways <BR>\n" );
document.write( "to solve it.<BR>\n" );
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document.write( "1. One unknown letting x = no of ml. of weaker solution and 40-x = no of ml. of stronger solution.<BR>\n" );
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document.write( "That equation would be .12(x) + .32(40-x) = .2(40)<BR>\n" );
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document.write( "2. One unknown letting x = no of ml. of stronger solution and 40-x = no of ml. of weaker solution.<BR>\n" );
document.write( "`<BR>\n" );
document.write( "That equation would be .12(40-x) + .32(x) = .2(40)<BR>\n" );
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document.write( "3. Two unknowns letting x = no of ml. of weaker solution and y = no of ml. of stronger solution.<BR>\n" );
document.write( "`<BR>\n" );
document.write( "This would be a system of two equations and two unknowns:\r<BR>\n" );
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document.write( "   x +    y =    40<BR>\n" );
document.write( ".12x + .32y = .2(40)<BR>\n" );
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document.write( "4. Two unknowns letting x = no of ml. of stronger solution and y = no of ml.<BR>\n" );
document.write( "of weaker solution.\r<BR>\n" );
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document.write( "This would be a system of two equations and two unknowns:\r<BR>\n" );
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document.write( "   x +    y =    40<BR>\n" );
document.write( ".32x + .12y = .2(40)<BR>\n" );
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document.write( "For any of these four ways, the answer is 24 ml of the weaker solution<BR>\n" );
document.write( "and 16 ml of the stronger solution.\r<BR>\n" );
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document.write( "Edwin<BR>\n" );
document.write( "AnlytcPhil@aol.com </SPAN>\n" );
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