document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=172268>Question 172268</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A high-speed copier can copy a certain report in 10 hours. An older copier requires 15 hours to do the same task. How long would it take to copy the report with both copiers operating? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #127246 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=127246\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A high-speed copier can copy a certain report in 10 hours. An older copier requires 15 hours to do the same task. How long would it take to copy the report with both copiers operating?<BR>\n" );
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document.write( "You have to figure what part of the job each does per hour.<BR>\n" );
document.write( "One does 1/10 per hour, the other 1/15 per hour.  Add those to get<BR>\n" );
document.write( "(1/10) + (1/15) = 25/150 = 1/6<BR>\n" );
document.write( "1/6 of the job per hour means it will take 6 hours.<BR>\n" );
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document.write( "A shortcut for this type of problem (with 2 elements) is the product divided by the sum.<BR>\n" );
document.write( "10*15/(10+15) = 150/25 = 6 hours.\r<BR>\n" );
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