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

Question : Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, whereas pipe C can empty the full tank in 40 hours. All three pipes are opened together, but pipe C is closed after 10 hours. After how many hours will the remaining part of the tank be filled?

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

Option 2: $2$

Option 3: $5 \frac{1}{2}$

Option 4: $5$

Question : Pipes A and B can fill a tank in 16 hours and 24 hours, respectively, whereas pipe C can empty the full tank in 40 hours. All three pipes are opened together, but pipe A is closed after 10 hours. After how many hours will the remaining part of the tank be filled?

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

Option 2: $10$

Option 3: $20$

Option 4: $15\frac{1}{2}$

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 and B can fill a tank in 36 hours and 48 hours, respectively. Both pipes are opened together for 9 hours and then A is closed. Pipe B alone will fill the remaining part of the tank now in:

Option 1: $20 \frac{1}{2}$ hours

Option 2: $25$ hours

Option 3: $27$ hours

Option 4: $24$ hours