Question : Pipes P and Q can fill a tank in 18 and 27 minutes, respectively, whereas pipe R can empty the full tank in 54 minutes. P and Q were opened together for 6 minutes and then closed and R was opened. The tank was emptied by R alone in:
Option 1: 35 minutes
Option 2: 45 minutes
Option 3: 30 minutes
Option 4: 40 minutes
Correct Answer: 30 minutes
Solution : Given: Pipe P filling time = 18 minutes Pipe Q filling time = 27 minutes Pipe R empty time = 54 minutes P and Q opened for 6 minutes. Now, Capacity of tank = LCM of 18, 27, and 54 = 54 units Efficiency of P = $\frac{54}{18}$ = 3 Efficiency of Q = $\frac{54}{27}$ = 2 Efficiency of R = $\frac{54}{54}$ = 1 Work done by P and Q in 6 min = $(3 + 2)\times 6 = 30$ Pipe R empty the tank = $\frac{30}{1} = 30$ min Hence the correct answer is 30 minutes.
Result | Eligibility | Application | Selection Process | Cutoff | Admit Card | Preparation Tips
Question : Pipes A and B can fill a tank in 18 minutes and $22 \frac{1}{2}$ minutes, respectively while pipe C can empty the full tank in 12 minutes. A and B are opened together for 6 minutes and then closed. Now C is opened. C alone will empty the tank in ____.
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?
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
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?
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?
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile