A water tank has 2 inlet and 1 outlet pipe attached to it. Inlet pipes...
There are 3 pipes;
If one pipe fills a water tank in x hours; Work done by the pipe in 1 hour is 1 / x.
So work done by 3 pipes I1 (5 hours inlet), I2 (10 hours inlet), I3 (4 hours outlet) be 1 / 5, 1 / 10 and -1 / 4.
So total work done by all pipes in 1 hour = 1 / 5 + 1 / 10 - 1 / 4 = 1 / 20.
Work done by all pipes after 15 hours = 15 / 20 = 3 / 4
Work left = 1 / 4
Now we have only I1 to fill the rest of tank which is 1 / 4 empty of its capacity.
Time taken by I1 = total work/ work done by I1 in 1 hour = (1 / 4)/(1 / 5) = 5 / 4 hours
= 1 hour and 15 minutes
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A water tank has 2 inlet and 1 outlet pipe attached to it. Inlet pipes...
There are 3 pipes;
If one pipe fills a water tank in x hours; Work done by the pipe in 1 hour is 1 / x.
So work done by 3 pipes I1 (5 hours inlet), I2 (10 hours inlet), I3 (4 hours outlet) be 1 / 5, 1 / 10 and -1 / 4.
So total work done by all pipes in 1 hour = 1 / 5 + 1 / 10 - 1 / 4 = 1 / 20.
Work done by all pipes after 15 hours = 15 / 20 = 3 / 4
Work left = 1 / 4
Now we have only I1 to fill the rest of tank which is 1 / 4 empty of its capacity.
Time taken by I1 = total work/ work done by I1 in 1 hour = (1 / 4)/(1 / 5) = 5 / 4 hours
= 1 hour and 15 minutes
A water tank has 2 inlet and 1 outlet pipe attached to it. Inlet pipes...
Given Data:
- Inlet pipe 1 fills the tank in 5 hours
- Inlet pipe 2 fills the tank in 10 hours
- Outlet pipe empties the tank in 4 hours
- All pipes were opened for 15 hours initially
Calculation:
- In 1 hour, the part of the tank filled by Inlet pipe 1 = 1/5
- In 1 hour, the part of the tank filled by Inlet pipe 2 = 1/10
- In 1 hour, the part of the tank emptied by Outlet pipe = 1/4
- In 15 hours, the tank is filled by (15/5 + 15/10 - 15/4) = 3 + 1.5 - 3.75 = 0.75
Remaining part of the tank to be filled:
- Since 0.75 part of the tank is already filled, the remaining part to be filled = 1 - 0.75 = 0.25
Time required to fill the remaining part:
- After closing the Outlet pipe and smaller Inlet pipe, only Inlet pipe 2 is filling the tank
- In 1 hour, Inlet pipe 2 fills 1/10 part of the tank
- Time required to fill 0.25 part of the tank = 0.25 / (1/10) = 2.5 hours = 2 hours and 30 minutes
Therefore, the tank requires 1 hour and 15 minutes more to fill it completely. Hence, the correct answer is option C.