Question 122248
It takes Tom 2 days to paint a house and it takes Leah 4 days and it takes Lisa 6 days.

We find one day work of each

Tom's 1 day work  = 1/2 of the work
Leah's 1 day work = 1/4 of the work
Lisa's 1 day work = 1/6 of the work

1 day work of all the three  =  1/2 + 1/4 + 1/6 = 11/12  of the work.

11/12 work is finished in = 1 day
1 work will be finished in 1/(11/12)  = 12/11  =  1 1/11  days

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