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Pull again or add a bullet and spin

Question

A six-chamber revolver holds two bullets in chambers separated by exactly one empty chamber. The first player spins once, fires at himself and survives. The second player may either (1) fire the next chamber as it is, or (2) load a third bullet, spin the cylinder at random, and then fire. Which option gives the second player the better survival chance? Answer 11, 22, or 33 if they are equally good.

Short answer

33 (equally good). With option 2, three of six chambers are loaded, so survival is 12\tfrac12. With option 1, the first shot was one of the 44 empty chambers, and exactly 22 of those are followed by another empty chamber, so survival is also 24=12\tfrac24=\tfrac12.

Adapted from QuantQuestions.io; question and answer rewritten by SelfMadeQuant.com.

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