railway RRB NTPC Mock Test Series 2024-25 (CBT 1 + CBT 2) Quantitative Aptitude Time and Work Pipe and Cistern
Pipes A and B can fill a tank in 12 minutes and 16 minutes respectively. Both A and B are opened for 4 minutes and then A is closed. How much extra time will B take to fill the tank completely?
1
\(\frac{{20}}{3}\) minutes
2
7 minutes
3
\(\frac{{21}}{4}\) minutes
4
6 minutes