SOLUTION: A manager on the job recognizes that he needs a computer task accomplished within 3.5 hours. Through observation he chooses his best employee (employee 1), and 2 others to work tog

Question 869525: A manager on the job recognizes that he needs a computer task accomplished within 3.5 hours. Through observation he chooses his best employee (employee 1), and 2 others to work together to accomplish this. He knows that employee 1 can complete the task in 9 hours working alone. While the others can complete the task in 12 hours and 13 hours, respectively, working alone. How long will it take the 3 employees working together to complete the computer task? Round your answer to 1 decimal place.
Answer by josgarithmetic(39620) (Show Source): You can put this solution on YOUR website!
These are each employee's work rates, in JOBS per HOUR:
Employee 1,
Employee 2,
Employee 3,

The combined rate of the three employees working together is the sum of their individual rates.

jobs per hour; but you will want the reciprocal, which will be in hours per job.

The final meaning that you are looking for is HOURS per JOB.
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