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There are 100 types of cards, each type with a number from 1 to 100 on it. Each minute I am given a random card. Random means that the number of my card has an equal chance of being 1,2,3,...,100. I stop when I have cards of each number, that is, I stop collecting once I have each number on at least one card. How many minutes is this process expected to take? That is, find the expected value of the number of minutes I have to wait.
E.g. I could potentially get duplicates so this method will take a lot more than 100 minutes. Once I get 99 different cards, I will stop as soon as I get the other one which I haven't got yet.
Thanks for helping everyone!