document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1164359>Question 1164359</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A coffee merchant combines coffee that costs $7 per pound with coffee that costs $3.30 per pound. How many pounds of each should be used to make 25 lb of a blend costing $5.89 per pound?<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 #788738 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=788738\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Another tutor has shown a solution by the standard algebraic method.  It is a method you should know and be able to use, as it is applicable to a wide range of similar two-part \"mixture\" problems.<br><BR>\n" );
document.write( "If speed of finding an answer is important (as in a timed math competition) and formal algebra is not required, here is a quick way to answer any question like this with logical reasoning and some mental arithmetic.<br><BR>\n" );
document.write( "(The mental arithmetic in this example might be a stretch for many students; but the path to the final answer will still be faster than with formal algebra.)<br><BR>\n" );
document.write( "Consider the three per-pound prices on a number line: 3.30, 5.89, and 7.00.<br><BR>\n" );
document.write( "The price of the mixture is 259/370 = 7/10 of the way from 3.30 to 7.00.  (3.30 to 7.00 is a difference of 3.70; 3.30 to 5.89 is a difference of 2.59.  2.59/3.70 = 259/370 = 7/10.)<br><BR>\n" );
document.write( "That means 7/10 of the mixture is the more expensive coffee.<br><BR>\n" );
document.write( "ANSWER: 7/10 of 25 pounds, or 17.5 pounds, of the more expensive coffee; the other 7.5 pounds of the less expensive.<br><BR>\n" );
document.write( "CHECK:<BR>\n" );
document.write( "17.5(7.00)+7.5(3.30) = 122.5+24.75 = 147.25<BR>\n" );
document.write( "25(5.89) = 147.25<br><BR>\n" );
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