When you have a Yissachar Zevulin partnership does Zevulin have to give exactly half of what he earns to Yissachar? In addition suppose Yissachar misses a day does he have to reimburse Zevulin?
No he doesn't Not all partners get an equal share, and not all profits go into the pockets of the partners. Here is an entire sefer written on the subject.
This is a very complex Halachik discussion that has been addressed by many people greater than us. One should read this article at Hakira to at least expose himself to some of the issues involved in this discussion.