document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=228229>Question 228229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One water pump can drain a lake in 9 hours. A newer model can drain the same lake in 6 hours. How long does it take for both water pumps together to drain the lake?\r<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 #169471 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=169471\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> One water pump can drain a lake in 9 hours. A newer model can drain the same lake in 6 hours. How long does it take for both water pumps together to drain the lake? <BR>\n" );
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document.write( "Let x = time in hours it takes for both to drain lake<BR>\n" );
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document.write( "x (1/9 + 1/6) = 1<BR>\n" );
document.write( "Multiply both sides by 54 (common denominator)<BR>\n" );
document.write( "x (6 + 9) = 54<BR>\n" );
document.write( "x(15) = 54<BR>\n" );
document.write( "x = 54/15<BR>\n" );
document.write( "x = 3.6 hours<BR>\n" );
document.write( "or<BR>\n" );
document.write( "x = 3 hours and 36 minutes\r<BR>\n" );
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