[gruez]

>In order to have 100% chance of getting Peach, I'd have to spend more than ~$3,400...

I don't think the author understands probabilities. They mention the probability of getting Peach in each roll is 0.25%, but assuming that each roll is independent, there's no way to guarantee (ie. "100% chance") that you get Peach, because it's possible to fail each roll no matter how many times you roll. If we take the author's dollar amount and work backwards to see what the overall probability is we end up with 91.2%, which is high but nowhere near 100%.

[objectivetruth]

They're not independent. (At least the last time I played,) they pull prizes out of the pool when you win them. So if there is 1 Peach in a 100-prize pipe, at most you have to buy 100.

[gruez]

Source? I searched around and the first source[1] seems to confirm what you say

>you can only receive a certain number of rewards from each rarity level per 100 Pipe uses

but further down it says

>Additionally, as long as you haven’t exhausted the quantity by rarity for its category, you can receive duplicates of a reward from the Pipe.

However, it also says

>In fact, you’re guaranteed to receive at least one reward of each type by the time you’ve used 100 Pipe pulls — though the exact reward you’ll get is random for all categories except High-End Spotlight.

I agree that each roll isn't independent and you can't model it as such, but I don't think there's any mechanism to guarantee you a prize given enough rolls, and I still suspect the author messed up the math.

[1] https://www.gamerevolution.com/guides/600991-mario-kart-tour...