Can somebody explain how these two problems are different? In the marbles one it doesn't matter if the person puts it back or not, the answer will be the same, why is that not the same for the candies one, why are both solved using two different methods?

[cylverixxx]

Data analysis progress quiz #9

As mentioned, the reason you aren’t just finding the probability of peach candies is the phrase: until he finds a peach one, at which point he stops. Had this not been there, you could certainly treat it like Question 6, because a bijection exists even though we’re trying to transition from a uniform probability to a non-uniform one. Basically, Question 6 has no restriction requiring the first 5 balls NOT be green, whereas Question 12 requires that the first two candy pieces are NOT peaches…

You can likely find your answer here.