document.write( "Question 867516: It takes John and his wife Tracey 3.5 hours to clean the house. Tracey and her daughter Susy can clean the house in 4 hours. When they all three work together they can clean the house in 3 hours. How long does it take Susy to clean the house by herself? \n" ); document.write( "
Algebra.Com's Answer #523254 by richwmiller(17219)\"\" \"About 
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1/j+1/t=1/3.5,
\n" ); document.write( "1/t+1/s=1/4,
\n" ); document.write( "1/t+1/j+1/s=1/3\r
\n" ); document.write( "\n" ); document.write( "1/t+1/j+1/s=1/3
\n" ); document.write( "1/t +1/s=1/4,
\n" ); document.write( "1/j=4/12-3/12
\n" ); document.write( "1/j=1/12
\n" ); document.write( "j=12\r
\n" ); document.write( "\n" ); document.write( "1/t+1/j+1/s=1/3
\n" ); document.write( "1/t+1/j=1/3.5
\n" ); document.write( "1/s=1/3 -1/3.5
\n" ); document.write( "1/s=3.5/10.5-3/10.5
\n" ); document.write( "1/s=1/21
\n" ); document.write( "s=21\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "1/t+1/s=1/4,
\n" ); document.write( "1/t+1/21=1/4
\n" ); document.write( "1/t=21/84-4/84=17/84
\n" ); document.write( "t=84/17\r
\n" ); document.write( "\n" ); document.write( "j = 12, s = 21, t = 84/17
\n" ); document.write( "j=12., s=21., t=4.94118
\n" ); document.write( " \n" ); document.write( "
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