document.write( "Question 684987: A can do a piece of work in 24 days, B in 32 days and C in 64 days. all begin to do it together, but A leaves after 6 days and B leaves 6 days before the completion of work. how many days did the work last ? \n" ); document.write( "
Algebra.Com's Answer #424305 by Jolliano(16)\"\" \"About 
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A = 24 days
\n" ); document.write( "B = 32 days
\n" ); document.write( "C = 64 days.\r
\n" ); document.write( "\n" ); document.write( "Fraction of work done in one day
\n" ); document.write( "by A = 1/24
\n" ); document.write( "by B = 1/32
\n" ); document.write( "by C = 1/64.\r
\n" ); document.write( "\n" ); document.write( "During the six days before A leaves,the fraction of the work that has been done is
\n" ); document.write( "6/24 = 1/4 by A
\n" ); document.write( "6/32 = 3/16 by B
\n" ); document.write( "6/64 = 3/32 by C.\r
\n" ); document.write( "\n" ); document.write( "Total fraction of work done in First 6 days =
\n" ); document.write( "1/4 + 3/16 + 3/32
\n" ); document.write( "=(8 + 6 + 3)/32
\n" ); document.write( "= 17/32.\r
\n" ); document.write( "\n" ); document.write( "Fraction of work left = 1 -17/32 = 15/32.\r
\n" ); document.write( "\n" ); document.write( "Since B leaves 6 days before the completion of the work,it means that C works alone for 6 days. The fraction of work C does alone in those 6 days is
\n" ); document.write( "6/64 = 3/32.\r
\n" ); document.write( "\n" ); document.write( "Therefore fraction of work done before B's departure =
\n" ); document.write( "15/32 - 3/32 = 12/32
\n" ); document.write( "=3/8.\r
\n" ); document.write( "\n" ); document.write( "Let X be the number of days in which B and C did 3/8 of the work.\r
\n" ); document.write( "\n" ); document.write( "Therefore,
\n" ); document.write( "x/32 is done by B
\n" ); document.write( "and x/64 is done by C.\r
\n" ); document.write( "\n" ); document.write( "This shows that
\n" ); document.write( "x/32 + x/64 = 3/8
\n" ); document.write( "Multiply through by 64
\n" ); document.write( "2x + x = 3 * 8
\n" ); document.write( "3x = 24
\n" ); document.write( "x = 24/3 = 8 days.
\n" ); document.write( "Total number of days
\n" ); document.write( "= 6 + 8 + 6 = 20 days.
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