document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=79963>Question 79963</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 49. One pipe can fill a tank in 8 minutes and a second pipe in 12 minutes. If the tank is empty, how long will it take both pipes to fill it?		<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 #57338 by </B><A HREF=/tutors/aboutme.mpl?userid=doctor_who><B>doctor_who(15)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=doctor_who><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=57338\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We don't know the volume of the tank, so let's say it has a capacity of G gallons.<BR>\n" );
document.write( "If the first pipe can fill the tank in 8 minutes, then the flow rate of the pipe is G/8 gallons per minute.<BR>\n" );
document.write( "Likewise, the flow rate of the second pipe is G/12 gallons per minute.<BR>\n" );
document.write( "That means the combined flow rate is (G/8) + (G/12) gallons per minute.<BR>\n" );
document.write( "Now, put them over a common denominator of 24 and simplify :<BR>\n" );
document.write( "(G/8) + (G/12) = 3G/24 + 2G/24<BR>\n" );
document.write( "= (5/24)G.<BR>\n" );
document.write( "So every minute, 5/24 of the tank gets filled by both pipes together.<BR>\n" );
document.write( "Therefore, in 24/5 minutes, the whole tank will be filled.<BR>\n" );
document.write( "24/5 minutes = 4 minutes and 48 seconds  (ANSWER)   </SPAN>\n" );
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