document.write( "Question 1013984: A takes 10 more days to do a job than B they both do a job in 12 days. in how many days B will take to complete the work if he works alone?? \n" ); document.write( "

Algebra.Com's Answer #630283 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "A takes 10 more days to do a job than B. They both do a job in 12 days.
\n" ); document.write( "In how many days B will take to complete the work if he works alone??
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document.write( "Let a = # of days for A to do the job working alone, and\r\n" );
document.write( "Let b = # of days for B to do the job working alone.\r\n" );
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document.write( "According to the condition, you have this system of two equations in two unknowns a and b:\r\n" );
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document.write( "a = b + 10,                 (1)\r\n" );
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document.write( ". = 1.           (2)\r\n" );
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document.write( "From (1), substitute a = b + 10 into (2). You will get\r\n" );
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document.write( ". = .    (3)\r\n" );
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document.write( "In (3), multiply both sides by b*(b+10) to get off the denominators. You will get\r\n" );
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document.write( "12*b + 12*(b+10) = b*(b+10),   or\r\n" );
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document.write( "24b + 120 = ,    or\r\n" );
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document.write( " = ,   or\r\n" );
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document.write( " = .\r\n" );
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document.write( "Factor left side:\r\n" );
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document.write( "(b-20)*(b+6) = 0.\r\n" );
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document.write( "The roots are b = 20 and b = -6.\r\n" );
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document.write( "Only positive b = 20 fits the condition.\r\n" );
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document.write( "Then a = b + 10 = 30.\r\n" );
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document.write( "Answer. It will take 20 days for B to complete the job working alone.\r\n" );
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\n" ); document.write( "\n" ); document.write( "For more details and more solved similar problems on joint work see the lessons\r
\n" ); document.write( "\n" ); document.write( " - Using fractions to solve word problems on joint work and
\n" ); document.write( " - Solving more complicated word problems on joint work\r
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