document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1101674>Question 1101674</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mr. Jackson is filling planter boxes with soil. He has soil that is 19% sand, and he buys 8 pounds of a commercial potting soil that is 22% sand. He mixes some of his soil with the 8 pounds of commercial potting soil. The resulting soil mixture is 21% sand. How many pounds of his soil did Mr. Jackson use?\r<BR>\n" );
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document.write( "A. 12 lb<BR>\n" );
document.write( "B. 4 lb<BR>\n" );
document.write( "C. 2 lb<BR>\n" );
document.write( "D. 8 lb </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #716272 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=716272\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let C denote the 19% solution and D denote the final 21% solution.<BR>\n" );
document.write( "We have 8 lbs of 22% solution.<BR>\n" );
document.write( "Using the method of alligation.<BR>\n" );
document.write( "1= 21 - 22<BR>\n" );
document.write( "2= 19 - 21<BR>\n" );
document.write( "E.g. There are 2 parts of C for every 1 parts of D<BR>\n" );
document.write( "then there are 8 parts of z, since (2/1)=8/z<BR>\n" );
document.write( "x= 4= 8/(2/1) lbs of 19% solution to add to your 8 lbs of 22% solution.<BR>\n" );
document.write( "y= 12= (8+4) lbs of the final 21% solution.<BR>\n" );
document.write( "check<BR>\n" );
document.write( "0.19 * 4 + 0.22 * 8 = 0.21*(8+4)<BR>\n" );
document.write( "0.76 + 1.76 = 0.21*(12)<BR>\n" );
document.write( "2.52 = 2.52<BR>\n" );
document.write( "ok<BR>\n" );
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document.write( "22         2       8 lbs of 22% solution\r\n" );
document.write( "      21          12 lbs of 21% solution\r\n" );
document.write( "19         1 1/2*8=4 lbs of 19% solution\r\n" );
document.write( "           3\r\n" );
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