In a tank, there are two inlet pipes, pipe A and pipe B which can fill the empty tank in 15 and 12 hours respectively. If both the inlets are open for 5 hrs and after that only pipe B is open, Find the time taken by inlet B to fill the remaining tank.
1
4 hrs
2
5 hrs
3
3 hrs
4
2 hrs
5
None of the above/More than one of the above