Question (7/28)
2 pipes A and B can fill a tank in 6 hours and 4 hours respectively. If they are opened on alternate hour with pipe A first, in how many hours the tank will be filled ?(A) 4 Hours
(B) 5 Hours
(C) 6 Hours
(D) 7 Hours
Question (8/28)
Two pipes A and B can fill a cistern in 12 minutes and 15 minutes respectively while a third pipe C can empty the full tank in 6 minutes. A and B are kept open for 5 minutes in the beginning and then C is also opened. In what time is the cistern emptied ?(A) 30 Minutes
(B) 35 Minutes
(C) 40 Minutes
(D) 45 Minutes