document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=272438>Question 272438</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many ounces of a 20% alcohol solution must be mixed with 15 ounces of a 25% alcohol solution to make a 23% alcohol solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #199290 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=199290\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In solving \"solutions\" problems, you have to keep track of the amount of pure stuff you need at the end.<BR>\n" );
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document.write( "x = ounces of 20% alcohol solution to add to the 15 oz of 25% solution<BR>\n" );
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document.write( "15 oz of a 25% solution = 3.75 oz of pure alcohol<BR>\n" );
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document.write( "The total amount can be described 15+x ounces.<BR>\n" );
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document.write( "We solve the problem in terms of the amount of pure alcohol<BR>\n" );
document.write( ".2x + 3.75 = .23(15+x)<BR>\n" );
document.write( ".2x + 3.75 = 3.45 + .23x<BR>\n" );
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document.write( "Subtracting .2x from both sides<BR>\n" );
document.write( "3.75 = .03x + 3.45<BR>\n" );
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document.write( "Subtracting 3.45 from both sides<BR>\n" );
document.write( ".3 = .03x<BR>\n" );
document.write( "Multiply by 100<BR>\n" );
document.write( "30 = 3x<BR>\n" );
document.write( "Divide by 3<BR>\n" );
document.write( "10 = x<BR>\n" );
document.write( "x = 10<BR>\n" );
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document.write( "So, you have to add 10 oz of 20% alcohol solution to 15 oz of 25% alcohol.<BR>\n" );
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document.write( "Always check your work.<BR>\n" );
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document.write( "At the end we would have 25 oz that we believe would be 23% alcohol.  If that is true, then we would have:<BR>\n" );
document.write( ".23 * 25 = 5.75 oz of pure alcohol in the solution.<BR>\n" );
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document.write( "We have shown (above) that we have 3.75 oz of pure alcohol in the 15 oz of 25% solution.<BR>\n" );
document.write( "How many oz of pure alcohol is there in 10 oz of 20% alcohol?<BR>\n" );
document.write( ".2*10 = 2 oz<BR>\n" );
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document.write( "3.75 + 2 = 5.75 oz, which is exactly what we needed<BR>\n" );
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document.write( "check the question to be sure you answer it at the end...<BR>\n" );
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document.write( "How many ounces do you need to add?<BR>\n" );
document.write( "You need to add 10 ounces of 20% alcohol solution. </SPAN>\n" );
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