Help me calculate a time difference
I hope this is an appropriate sub to ask this question. I haven't taken a math course in over 5 years so I'm very lost.
I'm writing a sci-fi story where there are two different dimensions. Time moves differently in each and I want to try and figure out how to calculate it.
Problem: Main character lives in Dimension A. They travel to Dimension B and stay there for 6 months (180 days). They go back to Dimension A to visit and find out they've been gone 9 years (3,285 days). If they visit Dimension A for 3 days, how much time would have passed in Dimension B before they go back?
I divided 3,285 by 180 and got 18.25. I then multiplied by 3 (for the days they were gone) and got (~55) 54.75 days. Is that correct or am I stupid?
EDIT: I know my username sounds like something a bot would make but I made this account like 2 years ago to lurk and never expected to post anything. I'm a human probably