Question 984793
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The job requires (45 workers)(10 days)=450 worker-days
In 4 days: (45 workers)(4 days)=180 worker-days
Still needed{ 450 worker-days - 180 worker-days=270 worker days
There are (45-15) 30 workers left.
For 30 workers to complete 270 worker-days:
(270 worker-days)/(30 workers)=9 days
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ANSWER: It will take 9 days to complete the work.