A can do a piece of work alone in 40 days. A and B together can do the same work in 10 days. C is 50% less efficient than B. In how many days can A and C together complete the same work?
Answer & explanation
Correct answer: option 3
A = 40 days, A + B = 10 days,
⇒ A + B = 4, (Efficiency)
⇒ 1 + B = 4,
⇒ B = 3,
C is 50% less efficient,
B : C = 3 : 1.5,
⇒ Time required by A + C to complete the total work = \(\frac{40}{1+1.5}\) = \(\frac{40}{2.5}\) = 16 days, ..(\(\frac{Work}{Efficiency}\) = Time)