Expected position of the second ace
Asked at Jane Street
A standard -card deck is shuffled uniformly and turned over one card at a time.
What is the expected position of the second ace? And on average, how many cards sit between consecutive aces?
Show a hint
The aces make equal gaps. The second ace sits after two gaps and one earlier ace.
Your answer
This one is open-ended. Work it through, then check your reasoning against the full solution.