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- Expected value of sums 9 answers
Consider a deck of $52$ cards. Let $X$ be the number of cards that are drawn until the first ace is chosen (e.g., if the first two cards are not an ace and the third card is an ace then $X=2$). Find $E(X)$.
Hint: Let $I_j$ denote be the indicator variable that is $1$ if the $j$th non-ace is chosen before the first ace and $0$ otherwise for $j=1,…,48$.
I don't really know how to approach this problem, the hint makes it sound more confusing to me.