document.write( "Question 1129779: Pipe A can fill a tank in five hours pipe B can fill it in two hours less than it takes pipe C, a drain pipe ,to empty the tank. with all three pipes open it takes three hours to fill the tank. how long would it take pipe C to empty it? \n" ); document.write( "

Algebra.Com's Answer #746398 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "Let x be the time for pipe C to empty the tank.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Then the time for the pipe B to fill the tank is (x+2) hours.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The rate of work for pipes A, B and C are  ,   and   of the tank volume per hour.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The balance equation is\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "     +  -  = ,    or\r\n" );
document.write( "\r\n" );
document.write( "     -  =  =  = .\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "To solve it, multiply both sides by  15*x*(x-2)  and simplify step by step.  You will get\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    15x - 15*(x-2) = 2x*(x-2)\r\n" );
document.write( "\r\n" );
document.write( "    30 = 2x^2 - 4x\r\n" );
document.write( "\r\n" );
document.write( "    2x^2 - 4x - 30 = 0\r\n" );
document.write( "\r\n" );
document.write( "    x^2 - 2x - 15 = 0\r\n" );
document.write( "\r\n" );
document.write( "    (x-5)*(x+3) = 0\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Answer.  x = 5 hours.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Check.   +  -  =   of the tank volume.   ! Correct !\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( "----------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Using Fractions to solve word problems on joint work \r
\n" ); document.write( "\n" ); document.write( "    - Solving more complicated word problems on joint work \r
\n" ); document.write( "\n" ); document.write( "    - Selected joint-work word problems from the archive \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Read them and get be trained in solving joint-work problems.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the topic
\n" ); document.write( "\"Rate of work and joint work problems\" of the section \"Word problems\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );