SOLUTION: If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa and Tom worked together to complete it ?

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Question 204947: If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa and Tom worked together to complete it ?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
If Sam can do a job in 4 days that Lisa can do in 6 days and Tom can do in 2 days, how long would the job take if Sam, Lisa and Tom worked together to complete it ?
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Sam does 1/4 job per day.
Lisa does 1/6 per day.
Tom does 1/2 per day.
Add those.
1/4 + 1/6 + 1/2 = 11/12
Together, they do 11/12 of the job per day, so it takes 12/11 days.
Together, 12/11 days.