document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=164585>Question 164585</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please answer my question:\r<BR>\n" );
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document.write( "Suppose you have 10 kg of cement, 5 kg of gravel, and 5 kg of sand for making concrete. Your concrete should contain 25% water by mass. How much water should you add? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #121279 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=121279\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of water needed\r<BR>\n" );
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document.write( "Total weight of the mixture=10+5+5+x=20+x<BR>\n" );
document.write( "And we are told that the water equals 25% of the mixture, so:\r<BR>\n" );
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document.write( "0.25(20+x)=x  get rid of parens (distributive law)<BR>\n" );
document.write( "5+0.25x=x subtract 0.25x from each isde<BR>\n" );
document.write( "5+0.25x-0.25x=x-0.25x  collect like terms<BR>\n" );
document.write( "5=0.75x  divide each side by 0.75<BR>\n" );
document.write( "x= 6.6667 or 6 2/3 kg----------------------amount of water needed\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "20+6.6667=26.6667<BR>\n" );
document.write( "0.25*26.66667= 6.6667<BR>\n" );
document.write( "6.6667=6.6667\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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