document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=251732>Question 251732</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How much soil containing 45% sand do you need to add to 1 ft3 of soil containing 15% sand in order to make a soil containing 35% sand? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #183423 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=183423\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of soil containing 45% sand that needs to be added<BR>\n" );
document.write( "Now we know that the amount of pure sand in the soil that's added (0.45x) plus the amount of pure sand in the 1 cu ft(0.15*1) has to equal the amount of pure sand in the final mixture(0.35(1+x)).  So our equation to solve is:<BR>\n" );
document.write( "0.45x+0.15*1=0.35(1+x)  get rid of parens<BR>\n" );
document.write( "0.45x+0.15=0.35+0.35x subtract 0.35x and also 0.15 from each side of the equation\r<BR>\n" );
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document.write( "0.45x-0.35x+0.15-0.15=0.35x-0.35x+0.35-0.15  collect like terms<BR>\n" );
document.write( "0.10x=0.20<BR>\n" );
document.write( "x=2 cu ft-------------amount of soil containing 45% sand that needs to be added\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "0.45*2+0.15*1=0.35(2+1)<BR>\n" );
document.write( "0.90+0.15=1.05<BR>\n" );
document.write( "1.05=1.05\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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