An inlet pipe can fill a tank in 4 hours and an outlet pipe can empty ...
Given:
Time taken by inlet pipe to fill the tank = 4 hours
Time taken by outlet pipe to empty 3/7 of a tank = 3 hours
Formula used:
Efficiency = Total work/Time taken
Calculation:
LCM of 4 and 7 = 28 = Total work
Efficiency of inlet pipe = 28/4 = 7 work
Efficiency of outlet pipe = 28/7 = 4 work
Work done in 2 hours = (7 – 4) = 3 work
Time taken to do 27 work = (2/3) × 27 hours
⇒ 18 hours
Time taken more to complete remaining 1 work = 1/7 hour
Total time taken = 18 + (1/7) hours
⇒ 127/7 hours
∴ The total time taken to fill the tank is 127/7 hours
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An inlet pipe can fill a tank in 4 hours and an outlet pipe can empty ...
An inlet pipe can fill a tank in 4 hours and an outlet pipe can empty ...
To solve this problem, we can use the concept of work and rate. Let's break down the given information:
- The inlet pipe can fill the tank in 4 hours. This means that in one hour, the inlet pipe can fill 1/4 of the tank.
- The outlet pipe can empty 3/7 of the tank in 3 hours. This means that in one hour, the outlet pipe can empty 3/7 * (1/3) = 1/7 of the tank.
Now, let's consider the alternate working pattern of the pipes. In each cycle, the inlet pipe fills the tank and the outlet pipe empties the tank. We need to determine the time taken for the tank to be completely filled.
Let's assume that the time taken to fill the tank is T hours. In T hours, the inlet pipe can fill T/4 of the tank, and the outlet pipe can empty T/7 of the tank. Since the tank is completely filled at the end of T hours, we can set up the following equation:
T/4 - T/7 = 1
To solve this equation, we can find a common denominator and simplify:
(7T - 4T) / 28 = 1
3T / 28 = 1
Cross-multiplying, we get:
3T = 28
T = 28/3 = 9 1/3 hours
However, the options provided do not include 9 1/3 as a choice. To find the closest option, we can convert 9 1/3 to a mixed number:
9 1/3 = 27/3 + 1/3 = 28/3
Therefore, the closest option is 28/3 hours, which is equivalent to 9 1/3 hours. Thus, the correct answer is option B) 127/7 hours.