307.The Throw That Passes a Hundred
★★★random walksOptiver
A fair six-sided die is thrown repeatedly and the running total is tracked. Consider the first moment the total exceeds 100. What is the probability that the throw which took it past 100 showed a 2?
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The last throw is a 2 exactly when the running total had stopped at 99 or 100 beforehand. How often does a running total visit any particular value?
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