document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=746639>Question 746639</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An outlet pipe can empty a cistern in 18 hours. With cistern full, this pipe and a second pipe are opened and together they empty 3/5 of the cistern in 6 hours. If the first pipe is then shut off, how long will it take the second pipe to finish emptying the cistern? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #454504 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=454504\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An outlet pipe can empty a cistern in 18 hours.<BR>\n" );
document.write( " With cistern full, this pipe and a second pipe are opened and together they empty 3/5 of the cistern in 6 hours.<BR>\n" );
document.write( " If the first pipe is then shut off, how long will it take the second pipe to finish emptying the cistern?<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Let t = time required by the 2nd pipe to empty the cistern <BR>\n" );
document.write( "Let the completed job = 1 (An empty cistern)<BR>\n" );
document.write( ":<BR>\n" );
document.write( "\"this pipe and a second pipe are opened and together they empty 3/5 of the cistern in 6 hours.\"<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F18 ALIGN=MIDDLE  ALT=\"6%2F18\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2Ft ALIGN=MIDDLE  ALT=\"6%2Ft\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2F5 ALIGN=MIDDLE  ALT=\"3%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply by 90t, resulting in:<BR>\n" );
document.write( "5t(6) + 90(6) = 18t(3)<BR>\n" );
document.write( "30t + 540 = 54t<BR>\n" );
document.write( "540 = 54t - 30t<BR>\n" );
document.write( "540 = 24t<BR>\n" );
document.write( "t = 540/24<BR>\n" );
document.write( "t = 22.5 hr for the 2nd pipe to empty the cistern alone<BR>\n" );
document.write( ":<BR>\n" );
document.write( "\"If the first pipe is then shut off, how long will it take the second pipe to finish emptying the cistern\"<BR>\n" );
document.write( "Let f = time required for 2nd pipe to finish emptying the cistern<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%2F18 ALIGN=MIDDLE  ALT=\"6%2F18\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28f%2B6%29%29%2F22.5 ALIGN=MIDDLE  ALT=\"%28%28f%2B6%29%29%2F22.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply by the least common multiple of 18 and 22.5, 405, resulting in:<BR>\n" );
document.write( "22.5(6) + 18(f+6) = 405<BR>\n" );
document.write( "135 + 18f + 108 = 405<BR>\n" );
document.write( "18f = 405 - 135 - 108<BR>\n" );
document.write( "18f = 162<BR>\n" );
document.write( "f = 162/18<BR>\n" );
document.write( "f = 9 more hrs to finish<BR>\n" );
document.write( " </SPAN>\n" );
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