document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=742195>Question 742195</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One pipe can fill a tank in 20 minutes, while	<BR>\n" );
document.write( "another takes 30 minutes to fill the same tank. How long would it take the two pipes together to fill the tank?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #852660 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13292)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=852660\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Here is a different way of solving a problem like this.<br><BR>\n" );
document.write( "Consider the least common multiple of the two given times, which is 60 minutes.<br><BR>\n" );
document.write( "In 60 minutes, the first pipe could fill the tank 60/20 = 3 times.<BR>\n" );
document.write( "In 60 minutes, the second pipe could fill the tank 60/30 = 2 times.<BR>\n" );
document.write( "So in 60 minutes together the two pipes could fill the tank 3+2 = 5 times.<BR>\n" );
document.write( "So the time it takes the two pipes to fill the tank one time is 60/5 = 12 minutes.<br><BR>\n" );
document.write( "ANSWER: 12 minutes<br><BR>\n" );
document.write( "NOTE: Both this method and the method shown by the other tutor can be used to solve similar problems in which one pipe is trying to fill the tank while another pipe is trying to drain the tank.<br><BR>\n" );
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