Working independently at the same constant rate, 9 machines can fill an order in 20 hours. how many of these machines, working independently, would be needed to fill the same order in 45 hours?

4 machines

Step-by-step explanation:

In the given situation, the number of machines is inversely proportional to the time taken by them.

Given : 9 machines can fill an order in 20 hours.

Let n be the number of machines required to fill the same order in 45 hours.

Then , we have the following inverse variation equation:-

Hence, the 4 machines would be needed to fill the same order in 45 hours.

depends on how many days you are talking about

step-by-step explanation:

the answer is 31.27mph