A can do a work in 15 days. B is 25% more efficient than A. In how many days, working together A and B will complete the same work?
Answer & explanation
Correct answer: option 3
A = 15 days,
B is 25% more efficient than A. therefore,
⇒ A : B = 4 : 5 (Efficiency)
⇒ Total work = 4 x 15 = 60 units, ..(Efficiency × Days = Total work)
⇒ Time required by A + B to complete the work = \(\frac{60}{4+5}\) = \(\frac{60}{9}\) = \(\frac{20}{3}\) days, ..(\(\frac{Work}{Efficiency}\) = Time)