document.write( "Question 1206762: A and B together can complete a work in 12 days.
\n" ); document.write( "C alone can complete the same work in 20 days. B alone can complete the same work in 18 days.
\n" ); document.write( "How many days will it take to do the same work if A and C does it together? \n" ); document.write( "
Algebra.Com's Answer #844512 by MathTherapy(10552)\"\" \"About 
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document.write( "A and B together can complete a work in 12 days.\r\n" );
document.write( "C alone can complete the same work in 20 days. B alone can complete the same work in 18 days.\r\n" );
document.write( "How many days will it take to do the same work if A and C does it together?\r\n" );
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document.write( "Let time A takes to do job, alone, be A\r\n" );
document.write( "Then A does \"1%2FA\" of job in 1 day\r\n" );
document.write( "Since B takes 18 days to do the same job, alone, then B does \"%281%2F18%29%5Eth\" of job in 1 day\r\n" );
document.write( "Working together, A and B take 12 hours to complete the job, so we get: \"matrix%281%2C3%2C+1%2FA+%2B+1%2F18%2C+%22=%22%2C+1%2F12%29\" \r\n" );
document.write( "                                                                       36 + 2A = 3A ----- Multiplying by LCD, 36A\r\n" );
document.write( "                                                                            36 = 3A - 2A\r\n" );
document.write( "                                   Time A takes to do job, working alone, or A = 36 days \r\n" );
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document.write( "Since A and C, working alone, take 36 and 20 days, respectively, to do the job, A and C would perform \"matrix%281%2C3%2C+%281%2F36%29%5Eth%2C+and%2C+%281%2F20%29%5Eth%29\" of the job, respectively, in 1 day \r\n" );
document.write( "Let the number of days it takes A and C, working together, to complete the job, be T. \r\n" );
document.write( "                                 We then get: \"matrix%281%2C3%2C+1%2F36+%2B+1%2F20%2C+%22=%22%2C+1%2FT%29\"\r\n" );
document.write( "                                              5T + 9T = 180 ----- Multiplying by LCD, 180T\r\n" );
document.write( "                                                  14T = 180\r\n" );
document.write( "Time A and C take to do job, working together, or
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