Heads given the ends differ
A fair coin is flipped times. Given that the first and last flips came out opposite (one heads, one tails), what is the expected number of heads among all flips?
Show hints (2)+
- Opposite ends contribute exactly head, guaranteed.
- The middle three flips are unaffected by the condition: expected heads. Add.
Answer
Reveal answer →Final answer
2.5
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Asked at: Jane Street, Akuna Capital