A factory requires 42 machines to produce a given number of articles in 63 days. How many machines would be required to produce the same number of articles in 54 days?

63 days required to produce articles using 42 machines.
No. of machines required to produce the same number of articles in 54 days = 42 × 63 / 54 = 49
Therefore, 49 machines would be required to produce the articles in 54 days.