document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1135838>Question 1135838</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A new type of pump can drain a certain pool in 4<BR>\n" );
document.write( " hours. An older pump can drain the pool in <BR>\n" );
document.write( "6 hours. How long will it take both pumps working together to drain the pool? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #753563 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=753563\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A new type of pump can drain a certain pool in 4<BR>\n" );
document.write( " hours. An older pump can drain the pool in <BR>\n" );
document.write( "6 hours. How long will it take both pumps working together to drain the pool?<BR>\n" );
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document.write( "There's a shortcut for problems like this:<BR>\n" );
document.write( "4*6/(4+6) = 2.4 hours<BR>\n" );
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document.write( "Greenstamps' method is similar, but I wouldn't bother with the LCM, just use the product, 6*4 = 24.  Same result.<BR>\n" );
document.write( "Teachers and texts seem to be obsessed with LEAST common multiple, for no good reason.  Just wastes your time. </SPAN>\n" );
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