document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=33497>Question 33497</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I can't figure out the right equation for this problem...<BR>\n" );
document.write( "I tried setting it to: x/3 + x/9= 1 because similar problems in my homework used the same type of equation but it doesn't work out correctly...\r<BR>\n" );
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document.write( "A pool can be filled by a pipe in 3 hours. It takes three times as long for another pipe to empty the pool. How long will it take to fill the pool with both pipes open. <BR>\n" );
document.write( "thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #19866 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=19866\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Notice that one pipe is filling and the other is emptying the pool.<BR>\n" );
document.write( "Let \"x\" be the number of hours required to fill the pool.<BR>\n" );
document.write( "Filling pipe Data:<BR>\n" );
document.write( "  time to fill= 3 hr   rate= (1/3)job/hr  work done= (1/3)x<BR>\n" );
document.write( "Emptying pipe Data:<BR>\n" );
document.write( "  time to empty=9 hr   rate= (1/9)job/hr  work done = (1/9)x<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "  fill  - emptying = 1 job<BR>\n" );
document.write( "Let \"x\" be the number of hours the job takes.<BR>\n" );
document.write( "  (1/3)x - (1/9)x = 1<BR>\n" );
document.write( "  3x - x = 9<BR>\n" );
document.write( "2x=9<BR>\n" );
document.write( "x=4.5 hours (pool will be full after 4.5 hours)<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "   </SPAN>\n" );
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