document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=282711>Question 282711</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Four gallons of a 45% acid solution is obtained by mixing a 90% solution with a 30% solution. How many gallons of each solution must be used to obtain the desired mixture? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #854177 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(53742)</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=854177\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Four gallons of a 45% acid solution is obtained by mixing a 90% solution with a 30% solution. <BR>\n" );
document.write( "How many gallons of each solution must be used to obtain the desired mixture?<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The solution by @mananth is fatally wrong due to wrong setup of the basic equation.\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 the quantity of 90% solution added be x<BR>\n" );
document.write( "the total solution obtained is 4 gallons<BR>\n" );
document.write( "So the remaining volume will be 30% solution<BR>\n" );
document.write( "=4-x gallons<BR>\n" );
document.write( "The sum of the acid content of mixed solutions is equal to acid content in the mixture<BR>\n" );
document.write( "0.9x + 0.3*(4-x) = 0.45*4<BR>\n" );
document.write( "0.9x + 1.2 - 0.3x = 1.80<BR>\n" );
document.write( "0.6x = 1.8 - 1.2<BR>\n" );
document.write( "0.6x = 0.6<BR>\n" );
document.write( "x = 0.6 / 0.6<BR>\n" );
document.write( "x = 1 gallons which is 90% acid solution<BR>\n" );
document.write( "Balance will be 30% acid solution.<BR>\n" );
document.write( "4 - 1 = 3 gallons\r<BR>\n" );
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document.write( "<U>ANSWER</U>.  &nbsp;&nbsp;1 gallon of the 90% solution and 3 gallons of the 30% solution.\r<BR>\n" );
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document.write( "<U>CHECK for concentration</U>.  &nbsp;&nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2A0.9%2B3%2A0.3%29%2F4 ALIGN=MIDDLE  ALT=\"%281%2A0.9%2B3%2A0.3%29%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 0.45,  or 45%.  &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;! Precisely correct !<BR>\n" );
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document.write( "Solved correctly.\r<BR>\n" );
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