document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=124343>Question 124343</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how many gallons of a 12% salt solution must be mixed with 6 gallons of a 20% salt soution to obtain a 15% salt solution? \r<BR>\n" );
document.write( "\n" );
document.write( "       100(.12)(x)+100(.20)(6)=.15%(100)\r<BR>\n" );
document.write( "\n" );
document.write( "12x+20(6)=15          12x+120=15<BR>\n" );
document.write( "                                        -120=-120<BR>\n" );
document.write( "12x=-105 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #91134 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=91134\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I HAVE A SUGGESTION: WHEN WORKING WORD PROBLEMS, LAY OUT THE PROBLEM IN A VERY BASIC AND ORDERLY FASHION.  I NEED TO KNOW WHAT x STANDS FOR, FOR EXAMPLE.\r<BR>\n" );
document.write( "\n" );
document.write( "Let x=number of gal of 12% solution needed<BR>\n" );
document.write( "Then (6+x) is the number of gal in the final 15% mixture\r<BR>\n" );
document.write( "\n" );
document.write( "Now we know that the amount of pure salt in the 12% solution(0.12x)plus the amount of pure salt in the 6 gal of 20% solution (6*0.20) has to equal the amount of pure salt in the final mixture(6+x)*(0.15).  So our equation to solve is:\r<BR>\n" );
document.write( "\n" );
document.write( "0.12x+0.20(6)=0.15(6+x)  get rid of parens<BR>\n" );
document.write( "0.12x+1.2=0.9+0.15x  subtract 0.9 and also 0.12x from both sides\r<BR>\n" );
document.write( "\n" );
document.write( "0.12x-0.12x+1.2-0.9=0.9-0.9+0.15x-0.12x  collect like terms\r<BR>\n" );
document.write( "\n" );
document.write( "0.3=0.03x  divide both sides by 0.03\r<BR>\n" );
document.write( "\n" );
document.write( "x=10 gal--------------amount of 12% solution needed\r<BR>\n" );
document.write( "\n" );
document.write( "CK<BR>\n" );
document.write( "0.12*10+0.20*6=(6+10)*0.15<BR>\n" );
document.write( "1.2+1.2=2.4<BR>\n" );
document.write( "2.4=2.4\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Hope this helps---ptaylor\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );