document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=295596>Question 295596</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many ounces of pure alcohol must be added to 40 ounces of a 70% alcohol solution to produce an 85% 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 #854264 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(53875)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=854264\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "How many ounces of pure alcohol must be added to 40 ounces of a 70% alcohol solution <BR>\n" );
document.write( "to produce an 85% alcohol solution?<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The solution in the post by @mananth is incorrect.\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;I came to bring a correct solution.\r<BR>\n" );
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document.write( "let quantity of pure alcohol to be added be x ounces<BR>\n" );
document.write( "70% alcohol is 40 ounces<BR>\n" );
document.write( "the total will be x+40 ounces<BR>\n" );
document.write( "x + 0.7*40 = (x+40)*0.85<BR>\n" );
document.write( "x + 28 = 0.85x + 34<BR>\n" );
document.write( "0.15x = 34 - 28<BR>\n" );
document.write( "0.15x = 6<BR>\n" );
document.write( "x = 6/0.15 = 40.\r<BR>\n" );
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document.write( "<U>ANSWER</U>.  &nbsp;&nbsp;40 &nbsp;ounces of pure alcohol must be added.\r<BR>\n" );
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document.write( "<U>CHECK</U> &nbsp;&nbsp;for the concentration: &nbsp;&nbsp;&nbsp;&nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2840+%2B+0.7%2A40%29%2F%2840%2B40%29 ALIGN=MIDDLE  ALT=\"%2840+%2B+0.7%2A40%29%2F%2840%2B40%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 0.85  &nbsp;&nbsp;! &nbsp;Precisely correct &nbsp;!\r<BR>\n" );
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document.write( "Solved correctly.\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Notice that &nbsp;85% &nbsp;concentration is precisely midpoint between &nbsp;70% &nbsp;and &nbsp;100%, \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;so the answer is obvious and can be guessed &nbsp;MENTALLY.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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