5 men can complete a work in 12 days, and 6 women can complete the same work in 20 days. In how many days can 1 man and 1 woman together complete this work?
Answer & explanation
Correct answer: option 3
Given,
5M x 12 = 6W x 20
⇒ M = 2W
⇒ M : W = 2 : 1 (Efficiency)
⇒ Total work = 5(2) x 12 = 120 units,
⇒ Time required by 1 man and 1 woman to complete total work = \(\frac{120}{1(2) + 1(1)}\) = \(\frac{120}{3}\) = 40 days, ..(\(\frac{Work}{Efficiency}\) = Time)