1. 8 emptying pipes and 18 filling pipes are connected to the tank of 750 litres. Each emptying pipe can alone empty the tank in 30 minutes and each filling pipe can alone fill the tank in 50 minutes. If all the pipes are opened together, then find the quantity of tank that is filled in 1 minute?
A) 35 B) 14 C) 70 D) 140 E) 105
2. Two pipes Aand B can fill a tank in 40 min and 56 min respectively. If both the pipes are opened together and the tank is filled in 25 min. Then, after how many minutes before the tank is full, pipe B is turned off?
A) 2 min B) 4 min C) 6 min D) 8 min E) 1 min
3. A large cistern can be filled by two pipes K and L. How many minutes will it take to fill the cistern from an empty state if L is used for half the time and K and Lfill it together for the other half? (Note: K and L can fill the tank in 15 and 10 min respectively)
A) 7.5 min B) 4.5 min C) 4 min D) 5 min E) 8 min
4. Pipe P alone can fill a tank in 32 hours and pipe Q alone can fill the same tank in ‘N’ hours. Pipe R alone can empty the tank in 24 hours. If all three pipes open together in the tank, then takes 480/7 hours to fill the tank. Find the value of ‘N’.
A) 25 B) 30 C) 15 D) 40 E) 60
5. Three pipes A, B and C were connected to the tank, and only 1 of them fills the tank and rest two are to make the tank empty. The time taken by pipes to fill or empty the tank is 15 mins, 30 mins and 60 mins respectively. If all the pipes were opened simultaneously and the tank got filled. Find the time in which the tank was filled.
A) 40 min B) 45 min C) 60 min D) 100 min E) 30 min
6. Three pipes A, B, and C can fill the tank in 7 hours. After working at it together for 3 hours, C is closed and A and B can fill there maining part in 5 hours. Find the number of hours taken by C alone to fill the tank.
A) 13 B) 35 C) 50 D) 22 E) 48
Key
1-C 2-B 3-A 4-D 5-C 6-B
