document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1024233>Question 1024233</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A chemist needs 500 milliliters of a 20% acid and 80% water mix for a chemistry experiment. The chemist combines X milliliters of a 10% acid and 90% water mix and Y milliliters of a 30% acid and 70% water mix to make the 20% acid and 80% water mix. \r<BR>\n" );
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document.write( "The chemists also needs 500 milliliters of a 15% acid and 85% water mix. Does the chemist need more of the 10% acid and 90% water mix than the 30% acid and 70% water mix to make this new mix? Explain.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #639730 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=639730\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> No need to mention the water part.\r<BR>\n" );
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document.write( "A chemist needs 500 milliliters of a 20% acid for a chemistry experiment. The chemist combines X milliliters of a 10% acid and Y milliliters of 30% acid to make the 20% acid. <BR>\n" );
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document.write( "You didn't ask a question.<BR>\n" );
document.write( "20% is the average of 10% & 30% --> equal parts.<BR>\n" );
document.write( "x = y = 250 ml\r<BR>\n" );
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document.write( "The chemists also needs 500 milliliters of 15% acid. Does the chemist need more of the 10% acid than the 30% acid to make this new mix? Explain.<BR>\n" );
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document.write( "Yes, he needs more 10%.<BR>\n" );
document.write( "Equal parts gives the average, 20%.<BR>\n" );
document.write( "More 10% --> lower than average concentration of the mix.<BR>\n" );
document.write( "More 30% --> higher than average concentration of the mix.<BR>\n" );
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document.write( "In math terms:<BR>\n" );
document.write( "x + y = 500 --> y = 500-x<BR>\n" );
document.write( "10x + 30*(500-x) = 500*C where C is the %age of the mix.<BR>\n" );
document.write( "15000 - 20x = 500*C<BR>\n" );
document.write( "C = 30 - x/25 (0 <= x <= 500)<BR>\n" );
document.write( "--> Increasing x decreases C\r<BR>\n" );
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