Answer:
56 Machines
Explanation:
To solve this problem we need to use the rules of ratio and proportion.
We have:
84 Machines : 32 Days
x : 21 Days
Let x = number of machines required
84:32 can also be

x : 21 can also be

Now we can solve for x by first cross multiplying.
=

32x = (84)(21)
32x = 1764
Now to find for x, we have to divide both sides by 32

x = 55.125
Now since we cannot have 1/8th of a machine we round up to 56.
We need 56 machines to produce the same number of articles in 21 days.