AFCAT I 22 Jan 2025 Shift 1 Paper

As per the question,
Two taps A and B can fill a tank alone in 6 hours and 9 hours respectively.
The portion of the tank that can be filled by tap‌A in 1 hour is ‌

1

6

The portion of the tank that can be filled by tap B in 1 hour is ‌

1

6

Also,
A third tap C alone can empty the same tank in 18 hours.
The portion of the tank that can be emptied by tap C in 1 hour is ‌

1

18

If all three taps are opened together, then the portion of the tank that can be filled in 1 hour is as follows,
‌‌

1

6

+‌

1

9

=‌

1

18

‌‌

3+2−1

18

=‌

2

9

Now, the time taken to fill the tank if three taps are opened together will be,
‌

1

2∕9

‌ hours ‌=4.5‌ hours ‌