document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=205579>Question 205579</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Three pipes can be used to fill a tank. It is filled in 10 hours using only the first pipe,in 12 hours using only the second pipe and in 15 hours using only the third one. A pressure problem cuts the flow capacity of each pipe in half. It is then decided to use three pipes together. How long will it take to fill a tank?\r<BR>\n" );
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document.write( "(A)4 hrs (B) 5 hrs (C) 8 hrs  (D) 12 hrs (E) None of these </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #155195 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=155195\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Three pipes can be used to fill a tank. It is filled in 10 hours using only the first pipe,in 12 hours using only the second pipe and in 15 hours using only the third one. A pressure problem cuts the flow capacity of each pipe in half. It is then decided to use three pipes together. How long will it take to fill a tank?<BR>\n" );
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document.write( "Since pressure is halfed the times for each is doubled:<BR>\n" );
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document.write( "1st pipe DATA:<BR>\n" );
document.write( "time = 20 hr/job ; rate = 1/20 job/hr<BR>\n" );
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document.write( "2nd pipe DATA:<BR>\n" );
document.write( "time = 24 hr/job ; rate = 1/24 job/hr\r<BR>\n" );
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document.write( "3rd pipe DATA:<BR>\n" );
document.write( "time = 30 hr/job ; rate = 1/30 job/hr\r<BR>\n" );
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document.write( "Together DATA:<BR>\n" );
document.write( "time = x hr/job ; rate = 1/x job/hr<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "rate + rate + rate = together rate<BR>\n" );
document.write( "1/20 + 1/24 + 1/30 = 1/x<BR>\n" );
document.write( "(24*30x) + (20*30x) + (20*24x) = 20*24*30<BR>\n" );
document.write( "x = 8 hrs.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( "(A)4 hrs (B) 5 hrs (C) 8 hrs (D) 12 hrs (E) None of these<BR>\n" );
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