document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=317379>Question 317379</A>: <I><SPAN STYLE=\"word-break: break-all;\"> mix a solution that is 50% acid with a solution that is 100% water to make 4 liters of a solution that is 10% acid. How much of each solution is used?\r<BR>\n" );
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document.write( "This is what I have (4-x)*(50/100) = 4x*10/100<BR>\n" );
document.write( "       50(4-x) = 40<BR>\n" );
document.write( "       200-50x = 40<BR>\n" );
document.write( " 200(-200)-50X = 40-200 <BR>\n" );
document.write( "          -50x = -160<BR>\n" );
document.write( "          -50x = -160 <BR>\n" );
document.write( "           50     50<BR>\n" );
document.write( "            x = -3.2 <BR>\n" );
document.write( "So -3.2 liters of water with 0.8 liters of 50% solution to get 4 liters with a 10% percent solution of acid. \r<BR>\n" );
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document.write( "I'm not sure if this is right. I have been working on it for so long I keep making stupid mistakes.   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #227255 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=227255\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Garamond\" size=\"+2\">\r<BR>\n" );
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document.write( "You almost have it.  It is just that your answer comes up with the wrong sign.  Doesn't make much sense to add a negative amount of water to an acid solution, now does it?\r<BR>\n" );
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document.write( "You actually set the problem up correctly, but you made a small error when you divided both sides by 50.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \frac{-50x}{50}\ \neq\ x\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \frac{-50x}{50}\ =\ -x\">\r<BR>\n" );
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document.write( "So\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ -x\ =\ -3.2\">\r<BR>\n" );
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document.write( "and therefore\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ x\ =\ 3.2\">\r<BR>\n" );
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document.write( "Meaning 3.2 liters of water and 0.8 liters of the 50% acid solution.\r<BR>\n" );
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document.write( "There is a much less complex way to do this one.  First off, let <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE x\"> represent the amount of acid solution needed.  Then, realizing that 50% is the same as one-half, and 10 percent of 4 liters is 0.4 liters, you can write:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \frac{x}{2}\ =\ 0.4\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ x\ =\ 0.8\">\r<BR>\n" );
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document.write( "And we get the same answer:  0.8 liters of acid solution and 3.2 liters of water.\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi} + 1 = 0\"><BR>\n" );
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