a tank is filled with two taps.the first tap can fill the tank completely in 45min and the second tap can empty the full tank in 1 hr.if both the taps are opened alternately for one min,then in how many hrs the empty tank will be filled completely?

• ans is 5 hours 53 minutes
  Lcm of (45, 60)==>180
  pipe one => 180/45= 4(as rate)
  pipe two(empty)==> 180/60= -3(as rate)
  day one 4 ltrs
  day two -3 ltrs
  cycle of alternately in 2 two day 4-3=1 ltr
  => 180-4=176ltr(first time tank fill)
  so ... 176*2+1=353
  353/60= 5 hours 53 minutes
• 7 years agoHelpfull: Yes(7) No(3)
• ans is 6 hour.
  explanation
  1st pipe->45 minutes
  2nd pipe->60 minutes
  in two minutes they fill the tank 1/180(1/45-1/60=1/180)
  so the tank will be filled completely in 2*180 minutes which is equal to 6 hours(2*180/60)
  ans=6 hours
• 7 years agoHelpfull: Yes(5) No(2)
• ans is 360 mints or 6 hrs
• 7 years agoHelpfull: Yes(0) No(0)