two pipes fills a 50 l the same tank, the first tank rate 15 l/ h and the other is 10 l/h. the first pipe runs alone for 100 min. how long does the whole take?
Pipe A fills a 5liter tank at a rate of 15liter per hour. Pipe B fills the same thank at a rate of 10 l/h. Pipe A runs alone for 100 minutes then the two of them together finish filling up the tank. How long does the whole operation take?