Probably also due to a typo, the last then is of course a than, changed that one now.
For a deeper undertsanding you can read my post on upvote bots:
https://steemit.com/steemit/@likedeeler/to-bot-or-not-to-bot-buying-upvotes-on-steemit where the reward machanism is explained a bit.
But you can also just trust me and do 50/50 which you have been doing most of the time anyway.