document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=94774>Question 94774</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One brand of cleaner used to etch concrete is 20% acid. A stronger industrial strength cleaner is 40% acid. How many gallons of each cleaner should be mixed to produce 10 gallons of 26% acid solution?\r<BR>\n" );
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document.write( "How do I do this problem, very confused. Thanks tutors. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #69001 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=69001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Let x=number of gal of 20% acid needed\r<BR>\n" );
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document.write( "Then 10-x=number of gal of 40% acid needed\r<BR>\n" );
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document.write( "Now we know that the amount of pure acid in the 20% solution (0.20x) plus the amount of pure acid in the 40% solution (0.40(10-x)) has to equal the amount of pure acid in the final mixture (0.26*10).  So our equation to solve is:\r<BR>\n" );
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document.write( "0.20x+0.40(10-x)=0.26*10  get rid of parens\r<BR>\n" );
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document.write( "0.20x+4-0.40x=2.6  subtract 4 from both sides\r<BR>\n" );
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document.write( "0.20x+4-4-0.40x=2.6-4  collect like terms\r<BR>\n" );
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document.write( "-0.20x=-1.4  divide both sides by -0.20\r<BR>\n" );
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document.write( "x=7------------------------------number of gal of 20% solution needed\r<BR>\n" );
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document.write( "10-x=10-7=3--------------------number of gal of 40% solution needed\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "7+0.20+3*0.40=10*0.26\r<BR>\n" );
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document.write( "1.4+1.2+2.6<BR>\n" );
document.write( "2.6=2.6\r<BR>\n" );
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document.write( "Hope this helps--------------ptaylor </SPAN>\n" );
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