AP ICET 25 July 2022 Shift 1 Solved Paper

Two pipes $\mathrm{P}$ and $\mathrm{Q}$ can fill an empty tank individually in 18 minutes and 24 minutes respectively. Both are opened at a time and after sometime $\mathrm{Q}$ is closed and $\mathrm{P}$ is continued to fill the tank. If the tank is full in 12 minutes then the time (in minutes) for which the pipe $\mathrm{Q}$ is opened is