Opera PMS - Home Study Correction Exercise 19

[@donabelroma1974]

hi ive got question and i really need the answer pls. I split some billing today for example £134 , £34 goes to company and £100 guest paying it but when i did the split i put £100 . instead split new billing attached - 100 3x then £100? what i did wrong? why some negative and why posted 3x etc ?