document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=214842>Question 214842</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There are two small valves in the bottom of a tub filled with water.  If opened, one valve will empty the tub in three hours; the other will empty it in six hours.  If both valves are opened at the same time, how long will it take to empty the tub? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #162304 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=162304\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are two small valves in the bottom of a tub filled with water. If opened, one valve will empty the tub in three hours; the other will empty it in six hours. If both valves are opened at the same time, how long will it take to empty the tub?<BR>\n" );
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document.write( "The small one empties 1/6 of the tub per hour.<BR>\n" );
document.write( "The other one 1/3 per hour.<BR>\n" );
document.write( "Add them <BR>\n" );
document.write( "1/6 + 1/3 = 3/6 = 1/2 tub per hour.<BR>\n" );
document.write( "--> 2 hours.<BR>\n" );
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document.write( "A shortcut:  product/sum<BR>\n" );
document.write( "3*6/(3+6) = 18/9<BR>\n" );
document.write( "= 2 hours </SPAN>\n" );
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