This problem involves calculating the time taken to fill a tank when one tap fills it and another simultaneously empties it. We need to find the net filling rate.
When both taps are open, the net filling rate is the difference between the filling rate and the emptying rate:
Net Rate = (Rate of Tap A) - (Rate of Tap B)
Net Rate = $ \frac{1}{40} \, \text{tank/min} - \frac{1}{60} \, \text{tank/min} $
To subtract these fractions, find a common denominator, which is 120:
Net Rate = $ \left( \frac{1 \times 3}{40 \times 3} \right) - \left( \frac{1 \times 2}{60 \times 2} \right) \, \text{tank/min} $
Net Rate = $ \frac{3}{120} - \frac{2}{120} \, \text{tank/min} $
Net Rate = $ \frac{1}{120} \, \text{tank/min} $
The time taken to fill the tank is the reciprocal of the net filling rate:
Time = $ \frac{1}{\text{Net Rate}} $
Time = $ \frac{1}{\frac{1}{120} \, \text{tank/min}} $
Time = $ 120 $ minutes
Therefore, the time taken to fill the tank when both taps are opened simultaneously is 120 minutes.
Two taps can fill a cistern in 4 hours and 9 hours, respectively. A third tap can empty it in 9 hours. How long (in hours) will it take to fill one-fourth of the empty cistern if all the taps are opened together?
A cistern is filled by two taps, C and D, in 54 minutes and 81 minutes, respectively. There is also a drain E at the bottom. If all three are opened simultaneously, the cistern is filled in 108 minutes. In how many minutes can drain E alone empty the cistern? (up to two decimal places)
Two pipes A and B can independently fill a tank completely in 20 and 30 minutes respectively. If both the pipes are opened simultaneously, how much time will they take to fill the tank completely?
The compound interest on Rs. 64,000 for 3 years, compounded annually at 7.5% p.a. is
A water tank can be emptied in 40 minutes by a pipe of d 'diameter, so how long will it take for a 2d diameter pipe to be emptied?
Two pipes X and Y can fill an empty tank in 16 hours and 20 hours respectively. Pipe Z alone can empty the completely filled tank in 25 hours. Firstly both pipes X and Y are opened and after 6 hours pipe Z is also opened. What will be the total time (in hours) taken to completely fill the tank?
Pipe J can fill a tank in 48 hours and pipe K can fill the same tank in 72 hours. If both the pipes are opened alternately for one hour each and pipe K is opened for the first hour, then in how much time the tank will be full?