A plug flow reactor is designed to give 78% conversion for a second order

reaction of type

2A longrightarrow P .

This has the rate equation, - gamma_{A} = 0.4C_{A} ^ 2 mole/lit min. Pure 'A' is fed to the reactor at 8 lit/min. at a concentration of 0-8 mole/lit. But when the reactor was operated, based on this design, it was found that 25% of the initial reactor behaved as a CSTR, while the remaining behaved as a PFR. Find the conversion for this reactor. Neglect density changes.