document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=714420>Question 714420</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 100% concentrate is to be mixed with a mixture having a concentration of 30% to obtain 45 gallons of a mixture with a concentration of 75%. How much of the 100% concentrate will be needed? (Round your answer to one decimal place.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #438794 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=438794\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \"...to obtain 45 gallons of mixture.\"\r<BR>\n" );
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document.write( "Let x and y be the gallons of the 100% concentrate and the 30% strength mixture, respectively, to use.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2Ax%2B0.3y%29%2F45=0.75 ALIGN=MIDDLE  ALT=\"%281%2Ax%2B0.3y%29%2F45=0.75\"   DISABLED_style= \"max-width:90%; height:auto;\" > AND <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2By=45 ALIGN=MIDDLE  ALT=\"x%2By=45\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  Those are a system of simultaneous equations.  Solve for x and y.\r<BR>\n" );
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document.write( "The rational equation can be adjusted,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2B0.3y=45%2A0.75 ALIGN=MIDDLE  ALT=\"x%2B0.3y=45%2A0.75\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2B0.3y=33.75 ALIGN=MIDDLE  ALT=\"x%2B0.3y=33.75\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which might be more convenient to use.  Why?\r<BR>\n" );
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document.write( "Because the system is equivalently<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2B0.3y=33.75 ALIGN=MIDDLE  ALT=\"x%2B0.3y=33.75\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2By=45 ALIGN=MIDDLE  ALT=\"x%2By=45\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Subtract the first equation from the second equation and very fast solve for y.  Use the value found for y in the second equation to solve for and find the value for x. </SPAN>\n" );
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