document.write( "Question 107942: A,B, and C can finish a job in 6 days. If B and C work together, the job will take 9 days; if A and C work together, the job will take 8 days. In how many days can each man working alone do the job? I was thinking about the equation:
\n" ); document.write( "A+B+C/6=1 \n" ); document.write( "
Algebra.Com's Answer #78665 by edjones(8007)\"\" \"About 
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\n" ); document.write( "1/a+1/b+1/c=1/6 (1/6 means 1/6 of the job in 1 day)
\n" ); document.write( "1/b+1/c=1/9...1/b=1/9-1/c
\n" ); document.write( "1/a+1/c=1/8...1/a=1/8-1/c
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\n" ); document.write( "1/a+1/b+1/c=1/6
\n" ); document.write( "1/8-1/c+1/9-1/c+1/c=1/6
\n" ); document.write( "-1/c+1/8+1/9=1/6
\n" ); document.write( "-72+9c+8c=12c multiply both sides by 72
\n" ); document.write( "5c=72
\n" ); document.write( "c=72/5 days to do the job working alone.
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\n" ); document.write( "1/a=1/8-5/72
\n" ); document.write( "1/a=9/72-5/72=4/72
\n" ); document.write( "a=72/4 days
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\n" ); document.write( "1/b=1/9-5/72
\n" ); document.write( "1/b=8/72-5/72=3/72
\n" ); document.write( "b=72/3 days
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\n" ); document.write( "Check:
\n" ); document.write( "5/72+4/72+3/72=12/72=1/6
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\n" ); document.write( "Ed
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