document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=249329>Question 249329</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An oil tanker can be filled in 18h using one pump and 15h using a different pump. If both pumps are used, how long would it take to fill the tanker? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #181583 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=181583\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An oil tanker can be filled in 18h using one pump and 15h using a different pump. If both pumps are used, how long would it take to fill the tanker?<BR>\n" );
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document.write( "If you add 15 and 18 it's 33 hours.  That can't be right.<BR>\n" );
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document.write( "One pump does 1/15 of the tanker per hour.<BR>\n" );
document.write( "The other does 1/18 per hour.<BR>\n" );
document.write( "Together they do 1/15 + 1/18 per hour = 6/90 + 5/90<BR>\n" );
document.write( "= 11/90 per hour<BR>\n" );
document.write( "--> 90/11 hours per tanker<BR>\n" );
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document.write( "There's a shortcut, product/sum<BR>\n" );
document.write( "15*18/(15+18) = 270/33<BR>\n" );
document.write( "= 90/11 hours<BR>\n" );
document.write( "=~ 8.18 hours </SPAN>\n" );
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