Tap A can fill the tank in 20 hours and tap B can fill in 10 hours. An outlet tap C at the bottom can empty the tank in 15 hours and another outlet tap D, at the middle, can empty it in 25 hours. At first, taps A and C were opened for 15 hours and then B and D were also opened. After how much time, from the beginning, would the tank be filled?

• firstly A n C are open but as A can fill 1/20 in 1 hr whereas C can empty 1/15 therefore filling rate
• 10 years agoHelpfull: Yes(1) No(0)
• 40*60*6-20*20*6=40*40*x
  x=15/2 hr
• 11 years agoHelpfull: Yes(0) No(0)