state gov DSSSB Junior Assistant, Steno and LDC Mock Test 2023 - 24 Quantitative Aptitude Time and Work Pipe and Cistern
A swimming pool can be filled by two pipes in 20 minutes and 30 minutes respectively. Both the pipes are opened together in an empty swimming pool. After some time, the first pipe stopped working, and the remaining swimming pool was filled in 18 minutes. After how much time the first pipe stopped working?
1
5 minutes
2
4.8 minutes
3
10 minutes
4
12 minutes