document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=507710>Question 507710</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many liters of a 10% alcohol solution must be mixed with 40 liters of a 50% solution to get a 40% solution? \r<BR>\n" );
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document.write( "I got the answer 13.3 L, but I'm not sure that it's right. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #340704 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=340704\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> With mixture problems, you need to pay attention to how much 'pure' stuff you have and how much you need.<BR>\n" );
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document.write( "40 liters of 50% solution means you have 20 liters of 'pure' alcohol<BR>\n" );
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document.write( "x = liters of 10% solution is to be added until you have a final solution that is 40% alcohol.<BR>\n" );
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document.write( ".5(40) + .1(x) = .4(40+x)<BR>\n" );
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document.write( "multiply by 10 to remove decimals<BR>\n" );
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document.write( "5(40) + x = 4(40+x)<BR>\n" );
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document.write( "200 +x = 160 + 4x<BR>\n" );
document.write( "40 = 3x<BR>\n" );
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document.write( "x = 40/3 = 13 1/3 liters<BR>\n" );
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document.write( "Check this to be sure it is the answer.<BR>\n" );
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document.write( "40/3 * .1 = 4/3 liters of alcohol<BR>\n" );
document.write( "120/3 * .5 = 20 liters of alcohol<BR>\n" );
document.write( "= 21 1/3 liters of alcohol.<BR>\n" );
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document.write( "40 + 40/3 = 120/3 + 40/3 = 160/3<BR>\n" );
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document.write( "160/3*.4 = 64/3 = 21 1/3 liters of alcohol<BR>\n" );
document.write( "which is correct.<BR>\n" );
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document.write( "Answer:  Add 13 1/3 liters of 10% alcohol solution.<BR>\n" );
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document.write( "Done. </SPAN>\n" );
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