If 3 men or 6 women can do a work in 20 days, then 6 men and 8 women can do it in:

A. 5 days
B. 6 days
C. 8 days
D. 10 days

Solution:
3M = 6W → 1M = 2W
So, 6M + 8W = 12W + 8W = 20W
Given 6W → 20 days → total work = 6×20 = 120 woman-days
20W → 120 ÷ 20 = 6 days
Answer: B