If 6 oil tankers can be filled by a pipe in`4 1/2` hours, how long does the pipe take to fill 4 such oil tankers?

A tank can be filled by 5 pipes in 80 minutes. How long it will take to fill the tank by 8 pipes of same size?

A cistern can be filled by a tap in 6 hours and emptied by an outlet pipe in 8 hours. How long will it take to fill the cistern if both the tap and the pipe are opened together ?

A cistern can be filled by a tap in 6 hours and emptied by an outlet pipe in 8 hours. How long will it take to fill the cistern if both the tap and the pipe are opened together ?

A cistern can be filled by a tap in 6hours and emptied by an outlet pipe in 8 hours.How long will it take to fill the cistern if both the tap and the pipe are opened together?

If two pipes function together, the tank will be filled in 12 h. One pipe fills the tank in 10 h faster than the other. How many hours does the faster pipe take to fill up the tank?

If two pipes are put in operation simultaneously, the tank is filled in 24 min. One pipe fills the tank in 20 min faster than the other. How many hours does the faster pipe take to fill the tank?