document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=745188>Question 745188</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bill can clean his office in 4 hours. Bob can do the cleaning in 3. How many hours will it take them if they work together? \r<BR>\n" );
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document.write( "An inlet pipe can fill an artificial pond in 60 minutes, while an outlet pipe an empty it in 80. Through an error, both pipes are left on. How long will it take for the pond to fill?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #453756 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=453756\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'll do the first one to get you started\r<BR>\n" );
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document.write( "Let t = time it takes them to do the job together\r<BR>\n" );
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document.write( "1/4 + 1/3 = 1/t\r<BR>\n" );
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document.write( "3/12 + 4/12 = 1/t\r<BR>\n" );
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document.write( "7/12 = 1/t\r<BR>\n" );
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document.write( "7*t = 12*1\r<BR>\n" );
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document.write( "7t = 12\r<BR>\n" );
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document.write( "t = 12/7\r<BR>\n" );
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document.write( "t = 1 & 5/7\r<BR>\n" );
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document.write( "So it will take exactly 1 & 5/7 hours (roughly 1.714 hours or roughly 1 hour, 42.857 minutes) to do the job together  </SPAN>\n" );
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