P1 fills a tank in 30 hours whereas P2 empties the tank in 60 hours. If P1 is opened in the first hour and P2in the second hour and so on, what is the earliest time in which the tank is filled?

• answer is 120 days
  A fills for 60 days
  B emptys for 60 days
• 13 years agoHelpfull: Yes(1) No(7)
• 120hours
  let capacity of tank is 300L
  A fills in 30 hrs means it fills 10L in 1 hr
  B empties it in 6o hrs means it empties 5L in 1hr
  now by combine in first 2 hrs tank is filled 5L (as 10L filled by A & 5L emptied by B)
  i.e. in 1 hr tank is filled 2.5L
  hence to fill it completely upto 300L,
  300/2.5 = 120hrs
• 13 years agoHelpfull: Yes(1) No(2)
• 60 hrs
  p2 empty the tank in one hour by half of the p1 filled .so the time is double to p1 to fill the tank
• 13 years agoHelpfull: Yes(0) No(8)