document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1024647>Question 1024647</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A pharmacist wishes to mix a solution that is 5&#8203;% Minoxidil. She has  on hand 80 ml of a 2&#8203;% solution and wishes to add some 7&#8203;% solution to obtain the desired 5&#8203;% solution. How much 7&#8203;% solution should she&#8203; add? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #640046 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=640046\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> she wants to get a mix of 5% minoxidil.\r<BR>\n" );
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document.write( "she has 80 ml of 2% solution of minoxidil.\r<BR>\n" );
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document.write( "she has a certain quantity of 7% minoxidil solution on hand that she can use.\r<BR>\n" );
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document.write( "let x equal the amount of 7% solution that she has to add.\r<BR>\n" );
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document.write( "let y = the total amount of solution that she will wind up with.\r<BR>\n" );
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document.write( "you have two equations that need to be solved simultaneously.\r<BR>\n" );
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document.write( "they are:\r<BR>\n" );
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document.write( "total solution:\r<BR>\n" );
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document.write( "80 + x = y\r<BR>\n" );
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document.write( "total amount of minoxidil:\r<BR>\n" );
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document.write( ".02 * 80 + .07 * x = .05 * y\r<BR>\n" );
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document.write( "since y = 80 + x, then replace y with 80 + x in the second equation to get:\r<BR>\n" );
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document.write( ".02 * 80 + .07 * x = .05 * (80 + x)\r<BR>\n" );
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document.write( "simplify this equation to get:\r<BR>\n" );
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document.write( "1.6 + .07 * x = 4 + .05 * x\r<BR>\n" );
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document.write( "subtract 1.6 from both sides of the equation and subtract .05 * x from both sides of the equation to get:\r<BR>\n" );
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document.write( ".07 * x - .05 * x = 4 - 1.6\r<BR>\n" );
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document.write( "simplify to get .02 * x = 2.4\r<BR>\n" );
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document.write( "divide both sides of the equation by .02 to get x = 2.4 / .02 = 120.\r<BR>\n" );
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document.write( "she would need 120 ml of the 7% solution to get a 5% solution.\r<BR>\n" );
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document.write( "the total number of mls would be 80 + 120 = 200.\r<BR>\n" );
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document.write( "the total amount of minoxidil would be .02 * 80 + .07 * 120 = 1.6 + 8.4 = 10.\r<BR>\n" );
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document.write( "the percent of minoxidil in the final solution would be 10 / j200 = .05 * 100 = 5%.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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