Correct Answer: 16 days
Explanation:
(16M + 12W) x 20 = 18W x 40
=> 2M = 3W
Then, Convert all men into women
12M + 27W = 27 + 12 x 3/2W = 45W
Let number of days required be 'D'
=> 18 x 40 = 45 x D
=> D = 16 days.