state gov UP Police Head Operator (Radio Cadre) Mock Test Quantitative Aptitude Time and Work Pipe and Cistern
Pipes A and B can fill a tank in 30 hours and 45 hours, respectively while pipe C alone can empty the full tank in 20 hours. When the tank is full, C alone is opened for 8 hours and then closed and pipes A and B are opened together at the same time. Now, how much time will pipes A and B together take to fill the tank completely?
1
7.5 hours
2
8 hours
3
7.8 hours
4
7.2 hours