Sixteen men and twelve women can complete a work in 8 days, if 20 men can complete the same work in 16 days, in how many days 16 women can complete the same piece of work ?

Explanation:

16 men + 12 women complete the work in 8 days.

20 men complete the work in 16 days.

∴ 16×8 men + 12×8 women ≡20×16men

=> 128 men + 96 women ≡ 320 men

=> 96 women => 192 men

=> 1 woman = 2 men

∴ 16 women = 32 men

∴ M1\D1 = M2\D2

=> 20×16 = 32×D2

=>D2 = 20×16\32 = 10 days