A tank can be filled by two taps A and B in 5 hours and 15 hours respectively. Tap C can empty the tank in 5 hours. If all three taps are opened simultaneously at 7:00 AM, So at what time it takes to fill the tank completely?
1
07 : 00 PM
2
10 : 00 PM
3
09 : 00 PM
4
11 : 00 PM