Question
Fix positive integers $h$ and $t$. What is the expected number of flips of a fair coin needed in order to either have $h$ more heads flipped than tails or $t$ more tails flipped than heads? Submit the result when $t = 10$ and $h=8$.
medium Probability
Parity Streaks
A release-checked medium problem for training Coins, Expected Value/LOTUS, Random Walk.
Practice focus
This Probability problem is tagged Coins, Expected Value/LOTUS, Random Walk. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.
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