document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=435961>Question 435961</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Pipe A can fill a tank in 4 hours, and pipe B can fill the tank in 3 hours. With the tank empty, pipe A is turned on. One hour later, pipe B is turned on. How long will pipe B run before the tank is filled?\r<BR>\n" );
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document.write( "Please help me with this questions, thanks.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #301681 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><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=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=301681\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If pipe A can fill a tank in 4 hours, and it is left on for an hour, it will have filled 1/4 of the tank. Together , the pipes can fill 1/4+1/3 tank an hour.<BR>\n" );
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document.write( "(1/4)t+(1/3)t=3/4<BR>\n" );
document.write( "Multiply both sides by 12<BR>\n" );
document.write( "3t+4t=9<BR>\n" );
document.write( "7t=9<BR>\n" );
document.write( "t=9/7 hours<BR>\n" );
document.write( "Pipe B will run along with pipe A together for 9/7 hours before they fill the tank. </SPAN>\n" );
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