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Russian Roulette Firing Strategy

HardStatistics & Probability00:00
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Your question is Russian Roulette Firing Strategy. Take a moment with it on the right.

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Problem

You and another person are playing Russian roulette. In the first round, there is one bullet loaded randomly. The other person spins, pulls the trigger, and survives. Now it’s your turn: should you fire immediately, or spin again first? What changes if there are two bullets loaded randomly, and what if the two bullets are in adjacent chambers?

Assume a standard six-chamber revolver, chambers arranged cyclically, and an initially uniform random position after the first spin. Calculate the probability of a bullet when firing immediately and after spinning again for each loading arrangement. State the safer action and explain the conditioning introduced by the first person’s survival.