1. If a pipe can fill the tank within 6 hrs. But due to leak it takes 30 min more. Now the tank is full then how much time will it take to empty the tank thought the leak? a) 78 b) 56 c) 66 d) 59

• ANS: A. 78
  
  Asume x hours for the pipe to fully drain the tank.
  The pipe can fill the tank completely in 6 hours, it can fill 1/6 of the tank per hour.
  With the hole, the tank gets filled in 6.5 hours and, so, is filled at a rate of 1/6.5 of the tank per hour.
  
  Since the pipe leaks at a rate of 1/x of the tank per hour, we see that:
  1/6 - 1/x = 1/6.5 ==> x = 1/(1/6 - 1/6.5) = 78 hours.
  
  
• 12 years agoHelpfull: Yes(23) No(0)
• pipe fill the tank with 6hours means...it fill 1/6tank in 1hour
  due to leakage it takes 6.5 hours so..1/6.5 tank got filled in an hour..
  to find the leakage rate..let it be 1/x
  so 1/6-1/x=1/6.5
  1/6+1/6.5=1/x
  78 hours
• 12 years agoHelpfull: Yes(10) No(3)
• filling= 6hrs, leak=13/2hrs
  it can empty tank in 6*13/2*2=78hrs
• 12 years agoHelpfull: Yes(6) No(4)