document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172204>Question 1172204</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Eric wishes to mix together some common stone worth $0.10 per kilogram and some granite chips worth $0.15 per kilogram to produce a decorative garden mixture.  How much of each stone should be mixed to obtain 300 kg of a mixture worth $0.13 per kilogram? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #797157 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=797157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Tutor @josgarithmetic likes that formula with all those variables for solving mixture problems like this.<br><BR>\n" );
document.write( "If you use that method to solve mixture problems, you won't learn anything about problem solving.  Plugging numbers into a formula doesn't really teach you anything.<br><BR>\n" );
document.write( "Tutor @ikleyn shows a standard algebraic method for solving the problem.  If you pay attention to how the method works, you will learn something useful about problem solving using formal algebra.<br><BR>\n" );
document.write( "But if a quick and easy solution without formal algebra is acceptable, here is the fastest way to solve this, or any similar mixture problem.<br><BR>\n" );
document.write( "(1) The price per kg of the mixture $0,13, is 3/5 of the way from $0.10 to $0.15.  (If you don't see that, picture the three numbers 0.10, 0.13, and 0.15 on a number line....)<BR>\n" );
document.write( "(2) That means 3/5 of the mixture is the more expensive ingredient.<br><BR>\n" );
document.write( "ANSWER: 3/5 of 300kg, or 180kg, of the more expensive granite chips; the other 120kg is the common stone.<br><BR>\n" );
document.write( "CHECK:<BR>\n" );
document.write( "180(0.15)+120(0.10) 27+12 = 39<BR>\n" );
document.write( "300(0.13) = 39<br><BR>\n" );
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