Answers

2016-02-14T20:58:48+05:30
A+B work in 18 days
therefore, (A+B)'s 1 day work=1/18

(B+C) work in 24 days
therefore (C+B)'s 1 day work= 1/24

(A+C) work in 36 days
therefore (A+C)'s 1 day work= 1/36

therefore,(A+B+B+C+A+C)'s 1 day work=1/18 + 1/24 + 1/36=9/72
                2(A+B+C)=1/8
                 a+B+C=1/16

therefore,A,B,C do the work together in 1/(1/16)=16 days....
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