Question : A pump can fill a tank with water in 3 hours. Because of a leak, it took $3\frac{1}{3}$ hours to fill the tank. In how many hours can the leak alone drain all the water in the tank when it is full?

Option 1: 21

Option 2: 15

Option 3: 30

Option 4: 10

Question : A pump can fill a tank with water in 1 hour. Because of a leak, it took $1 \frac{1}{3}$ hours to fill the tank. In how many hours can the leak alone drain all the water in the tank when it is full?

Option 1: 5

Option 2: 1

Option 3: 2

Option 4: 4

Question : Two pipes can fill a tank in 15 hours and 4 hours, respectively, while a third pipe can empty it in 12 hours. How long (in hours) will it take to fill the empty tank if all three pipes are opened simultaneously?

Option 1: $\frac{50}{7}$

Option 2: $\frac{15}{7}$

Option 3: $\frac{30}{7}$

Option 4: $\frac{20}{7}$

Question : Pipes A and B can empty a full tank in 18 hours and 24 hours, respectively. Pipe C alone can fill the tank in 36 hours. If the tank is $\frac{5}{6}$ full and all the three pipes are opened together, then in how many hours will the tank be emptied?

Option 1: $10 \frac{1}{2}$

Option 2: $12 \frac{1}{2}$

Option 3: $10$

Option 4: $12$

Question : Pipes A, B and C can fill a tank in 10, 15 and 30 hours, respectively. D is an emptying pipe which alone can empty the full tank in $x$ hours. A, B and C are opened together for 3 hours and then closed. Now D is opened which alone empties the tank in 30 hours. What is the value of $x$?

Option 1: 50

Option 2: 40

Option 3: 60

Option 4: 45

Question : Pipes A, B and C can fill an empty tank in $\frac{30}{7}$ hours if all three pipes are opened simultaneously. A and B are filling pipes and C is an emptying pipe. Pipe A can fill the tank in 15 hours and pipe C can empty it in 12 hours. In how much time (in hours) can pipe B alone fill the empty tank?

Option 1: 3

Option 2: 5

Option 3: 6

Option 4: 4