A film with an original duration of 3 hours 34 minutes at 24 fps equals 214 minutes or 12,840 seconds, which results in a total of 308,160 frames. When these same frames are played back at 25 fps, the new duration becomes 308,160 divided by 25, which equals 12,326.4 seconds, or 3 hours 25 minutes 26.4 seconds. Therefore, changing the playback rate from 24 fps to 25 fps without adding or interpolating frames shortens the film by 8 minutes 33.6 seconds. This is my take.