Answer:
11days
Step-by-step explanation:
If A can do the job in 25days.
A's 1 day's job = 1/25
If B can do the job in 20days.
B's 1 day's job = 1/20
Therefore the job done by A and B together in 1day = 1/25 + 1/20 = 9/100
But they both work together for 5 days. So the job done by both of them in 5 days = 9/100 x 5 = 9/20
Since A left, the remaining job will be = 1 — 9/20 = 11/20
If B's 1 day's job = 1/20
Then B's x day's job = 11/20
B's xday = (11/20) / (1/20) = 11/20 x 20 = 11 days
Therefore, B can finish the remaining job in 11days
