document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=69703>Question 69703</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1. An executive nearing retirement made two investments totaling $15,000.  In one year, these investments yielded $1432 in simple interest.  Part of the money was invested at 9% and the rest at 10%.  How much was invested at each rate?\r<BR>\n" );
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document.write( "2. Two cars leave Salt Lake City, travelng in opoosite directions.  One car travels at a pseed of 80 km/h and the other at 96 hm/h.  In how many hours will they 528 km apart?\r<BR>\n" );
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document.write( "3.  McDonald's recently sold small soft drinks for $.87 meidum soft drinks for $1.08, and large soft drinks for $1.54.  During a lunchtime rush, Chris sold 40 soft dirnks for a total of $43.40.  The number of small and large drinks, combined, was 10 fewer than the number of medium drinks.  How many drinks of each size were sold?\r<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 #49663 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=49663\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. An executive nearing retirement made two investments totaling $15,000.  In one year, these investments yielded $1432 in simple interest.  Part of the money was invested at 9% and the rest at 10%.  How much was invested at each rate?<BR>\n" );
document.write( "Let amt. invested at 9% be \"x\";  Interest on this is 0.09x dollars<BR>\n" );
document.write( "Amt. invested at 10% is \"15000-x\" ; Interest on this is 0.1(15000-x)=1500-0.1x<BR>\n" );
document.write( "dollars<BR>\n" );
document.write( "EQUATION: <BR>\n" );
document.write( "interext + interest=1432 dollars<BR>\n" );
document.write( "0.09x + 1500-0.10x = 1432<BR>\n" );
document.write( "-0.01x = -68<BR>\n" );
document.write( "x=$6800 (amt invested at 9%)<BR>\n" );
document.write( "15000-6800=$8200 (amt invested at 10%<BR>\n" );
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document.write( "2. Two cars leave Salt Lake City, travelng in opoosite directions.  One car travels at a pseed of 80 km/h and the other at 96 hm/h.  In how many hours will they 528 km apart?<BR>\n" );
document.write( "let \"x\" be the number of hours before they meet.<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "80x + 96x = 528<BR>\n" );
document.write( "178x=528<BR>\n" );
document.write( "x=3 hours<BR>\n" );
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document.write( "3.  McDonald's recently sold small soft drinks for $.87 meidum soft drinks for $1.08, and large soft drinks for $1.54.  During a lunchtime rush, Chris sold 40 soft dirnks for a total of $43.40.  The number of small and large drinks, combined, was 10 fewer than the number of medium drinks.  How many drinks of each size were sold?\r<BR>\n" );
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document.write( "Let S,M,L be the number of small, medium, and large drinks.<BR>\n" );
document.write( "S+M+L=40<BR>\n" );
document.write( "87S+108M+154L=4340<BR>\n" );
document.write( "S-M+L=-10<BR>\n" );
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document.write( "Solve this system of three equations.<BR>\n" );
document.write( "I used a matrix method and got:<BR>\n" );
document.write( "S=10<BR>\n" );
document.write( "M=25<BR>\n" );
document.write( "L=5<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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