Time and Work
A, B and C can complete a piece of work in 21, 35 and 42 days, respectively. They started the work together but B and C left 7 days before the completion of the work. For how many days did B and C work?
One pipe can fill the tank in 9 minutes while another pipe can empty completely filled tank in 90 minutes. If both the pipes are operated together on empty tank, how long (in minutes) will it take to fill the tank completely?
Pipe A can fill a tank in 9 minutes, while pipe B can empty the completely filled tank in 10 minutes. Initially, pipe A is opened and after 3 minutes pipe B is also opened. In how much time (in minutes) will the remaining tank be filled completely?
A, B and C can complete a piece of work in 21, 35 and 42 days, respectively. They started the work together but B and C left 7 days before the completion of the work. For how many days did B and C work?
A, B and C can complete a piece of work in 21, 35 and 42 days, respectively. They started the work together but B and C left 7 days before the completion of the work. For how many days did B and C work?