document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=90992>Question 90992</A>: <I><SPAN STYLE=\"word-break: break-all;\"> When both copying machines A and B are working, 100 copies can be made in one minute.  In one minute, copiers A and C can make 140 copies.  If all three copy machines are working, 180 copies can be made in one minute.  How many copies per minute can each copier make? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66041 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=66041\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When both copying machines A and B are working, 100 copies can be made in one minute.  In one minute, copiers A and C can make 140 copies.  If all three copy machines are working, 180 copies can be made in one minute.  How many copies per minute can each copier make?<BR>\n" );
document.write( "Let A, B, C be the number of copies produced respectively by the machines in one minute.<BR>\n" );
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document.write( "Each one's production rate is 1/A, !/B, !/C<BR>\n" );
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document.write( "A + B = 100<BR>\n" );
document.write( "A + C = 140<BR>\n" );
document.write( "A + B + C = 180<BR>\n" );
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document.write( "(I used the matrix method on a TI-83 calculator to get:<BR>\n" );
document.write( "A = 60 copies per minute<BR>\n" );
document.write( "B = 40 copies per minute<BR>\n" );
document.write( "C = 80 copies per minute<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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