Q. Pipe A can fill a tank in 6 hours. due to leak at bottom it takes 9 hours to fill the tank. In what time the leak alone can empty the full tank?

Option
a) 16 hours
b) 15 hours
c) 18 hours
d) 17 hours

• let it fills 1l in 1 hr
  in 6 hr it fills 6l
  in 9 hr it fills 9 l
  in 9 hrs it leaks 3l
  in 1 hr it leaks 3/9=1/3 l
  1/3l leaks in 1 hr
  6 l leaks in 1*3*6=18 hr
• 8 years agoHelpfull: Yes(2) No(0)
• Leak alone can vacate the full tank in 18 hours.
  As per the data given Pipe A take 3 hrs more to fill the tank. In Three hours it can fill half the tank. This implies that the leak can vacate half the tank in 9 hours. So to fully vacate the tank the leak will take 18 hours.
• 8 years agoHelpfull: Yes(2) No(0)
• Let the capacity of the tank be 36 litres.
  When A alone is there, it fills 6 litres per hour.
  When the leak is open, it fills only 4 litres per hour, so 2 litres are leaking per hour because of the leak.
  So, the leak can empty the full tank in 36/2 = 18 hours.
  
  Answer is 18 hours
  
• 10 years agoHelpfull: Yes(0) No(4)
• 1/6-1/9=118
  ans 18
• 8 years agoHelpfull: Yes(0) No(1)
• Pipe A takes 6 hrs to fill it.
  the Leak takes x hrs to empty the tank.
  Lcm of the work done (total work done)=6x
  per hr work of A is 6x/6=x lts
  per hr work of leak=6x/(-x)=-6
  so,
  ((x+(-6)) lts)/(6x lts) =(1/9)
  i.e.
  (x-6)/6x=(1/9) => x=18 hrs
• 6 years agoHelpfull: Yes(0) No(0)
• To fill it take 1/6
  To fill due to leak it take (-1/9)
  1/6 + (-1/9)
  1/18
  Therefore 18 hr . Ans
• 5 years agoHelpfull: Yes(0) No(0)