document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=566089>Question 566089</A>: <I><SPAN STYLE=\"word-break: break-all;\"> One dran can empty pool in 20 hours, another in 25.  If both drains work, how long to empty pool? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #366122 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=366122\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=time required for both drains working together to drain the pool<BR>\n" );
document.write( "Then both drains working together drains at the rate of 1/x pool per hour<BR>\n" );
document.write( "One drain drains at the rate of 1/20 pool per hour<BR>\n" );
document.write( "Another drains at the rate of 1/25 pool per hour\r<BR>\n" );
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document.write( "Together they drain at the rate of 1/20 + 1/25 pool per hour, soooo\r<BR>\n" );
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document.write( "1/20+1/25=1/x  multiply each term by 100x<BR>\n" );
document.write( "5x+4x=100<BR>\n" );
document.write( "9x=100<BR>\n" );
document.write( "x=11.11 hours\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "In 11.11 hours one drains drains 11.11/20 of the pool<BR>\n" );
document.write( "The other drains 11.11/25 of the pool<BR>\n" );
document.write( "11.11/20 + 11.11/25 needs to equal 1 (1 pool, that is)<BR>\n" );
document.write( "55.55/100 + 44.44/100=99.99/100  Close enough\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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