Expected fives before the first six

You roll a fair die until you get your first $6$ . What is the expected number of $5$ s you roll before stopping?

Show hints (2)+

Only $\{5,6\}$ rolls matter; each is equally likely, stop on $6$ .
The number of $5$ s before the $6$ is geometric with mean $\tfrac{1/2}{1/2}=1$ .

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