A can finish a work in 20 days and B can finish the same work in 25 days. They begin together, but B left the work after 5 days. How many more days will A take to finish the remaining work?
Answer & explanation
Correct answer: option 1
A = 20 days, B = 25 days,
⇒ A + B worked for 5 days = (5 + 4) x 5 = 45 units, ..(Efficiency × Days = Total work)
⇒ Remaining work = 100 - 45 = 55 units,
⇒ Time required by A to complete the 55 units alone = \(\frac{55}{5}\) = 11 days. ..(\(\frac{Work}{Efficiency}\) = Time)
Therefore, A will complete the remaining work in 11 days.