The question is to find float for task H

I was told a quick way to calculate float is to locate task and subtract total duration days from critical path days. In this case 32-25=7 days.

What if there are tasks that are on multiple paths, how would you figure it out?
Thanks for the help

Start: Task A-Task C-Task F-Task G-End, Duration: 29 days
Start: Task B-Task D-Task E-Task H-Task I-End, Duration: 25 days
Start: Task B-Task D-Task E-Task G-End, Duration: 23 days
Start: Task B-Task C-Task F-Task G-End, Duration: 32 days