24
Q:
A) 49.5 min | B) 50 min |
C) 51 min | D) 52 min |
Answer: C) 51 min
Explanation:
Explanation:
The work to be done = Capacity of reservoir = 30 litres.
1st Minute ---> inlet pipe opened ---> 5 lit filled
2nd minute ---> inlet pipe closed; outlet pipe opened ---> 4 lit emptied
In 2 minutes (5 litres - 4 litres = 1lit) is filled into the reservoir.
It takes 2 minutes to fill 1lit ---> it takes 50 minutes to fill 25 litres into the reservoir.
In the 51st minute inlet pipe is opened and the reservoir is filled.