document.write( "Question 461969: Working alone Ann can clean the house in 7 hours. WOrking with Tom they can clean it in 4 hours. How long will it take Tom to clean the house alone? \n" ); document.write( "
Algebra.Com's Answer #316742 by stanbon(75887)\"\" \"About 
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Working alone Ann can clean the house in 7 hours.
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\n" ); document.write( "Ann's rate = 1/7 job/hr
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\n" ); document.write( "WOrking with Tom they can clean it in 4 hours.
\n" ); document.write( "Together rate = 1/4 job/hr
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\n" ); document.write( "How long will it take Tom to clean the house alone?
\n" ); document.write( "Tom's rate = 1/x job/hr
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\n" ); document.write( "Equation:
\n" ); document.write( "rate + rate = together rate
\n" ); document.write( "1/7 + 1/x = 1/4
\n" ); document.write( "4x + 28 = 7x
\n" ); document.write( "3x = 28
\n" ); document.write( "x = 28/3 hrs = 9 1/3 hrs = 9 hrs 20 minutes (Tom's time to do job alone)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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