How many days should it take the remaining 3 workers to build a barn?

9514 1404 393

Step-by-step explanation:

The effort required to complete a task is often estimated in terms of person·days. Amy's barn-building task takes an effort of ...

  (5 workers)(9 days) = 45 worker·days

If there are only 3 workers, the time required is ...

  time = (45 worker·days)/(3 workers) = 15 days

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If the barn is to be build in 7 days, the number of workers required is ...

  (45 worker·days)/(7 days) = 6 3/7 workers

A minimum of 7 workers are required to build the barn in 7 days or less. (6 workers will take 7 1/2 days, so aren't enough.)

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.