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?

Explanation

Let the number of machines be y and the number of days be x.


If the number of days decreases, the number of machines required will increase. So, they are inverse proportion.


Two numbers x and y are said to be in inverse proportion when an increase in one quantity decreases the other quantity and vice versa.


`xy = k or x = (1/y) k`


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