So, this is a bit odd. I think is a good opportunity to learn more about this subject since I'm really lacking.. in my game (sorry not an assignment) there are chests you can open, and for every chest there's a 1.69% chance of getting a "mystic" item. I want to be able to find out how long it would take (through calculations) to be certain of getting one. I've been thinking about it for awhile but I don't know how to solve it, I provided a photo of the percentages and such, but it won't let me show the whole thing.. I can type it out if needed. for context it takes only a little while to be able to get a chest, for 1000 coins.

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