SOLUTION: if three machines can complete a job in 8 hours, 5 hours, and 4 hours respectively, when they work alone, how long will it take the three working together to complete the job

SOLUTION: if three machines can complete a job in 8 hours, 5 hours, and 4 hours respectively, when they work alone, how long will it take the three working together to complete the job

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Question 951015: if three machines can complete a job in 8 hours, 5 hours, and 4 hours respectively, when they work alone, how long will it take the three working together to complete the job
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
The three are working together, meaning all three at the same time, meaning THE SUM OF THEIR RATES. The unit must be JOBS per HOUR.
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