If 30 men can complete a piece of work in 27 days, in what time 18 men can do another piece of work 3 times as greater?

Question: If 30 men can complete a piece of work in 27 days, in what time 18 men can do another piece of work 3 times as greater?

Solution:
30 men can do a piece of work in 27 days, and we know that men × days = total work
So, we can say that the total work = 30 × 27 = 810 units
Now ATQ,
18 men can do work 3 times greater than 810 units.
i.e., 18 men can do a work 3 × 810 = 2430 units in x days
Men × days = total work (2430 units)
⇒ 18 × x = 2430
∴ x = 2430/18 = 135 days