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Russian Roulette

ProbabilityHard
15 min
30 pts

Description

6-chamber revolver with 1 bullet fired empty. Choose to spin or pull trigger next and compute survival odds.

Game Rules

A revolver has 6 chambers, one bullet. The first shot was empty. You can either spin the cylinder again or pull the trigger. Which gives better survival odds?

Examples

If you spin: 1/6 chance of death

If you don't spin: 1/5 chance of death (5 chambers left, 1 bullet)

Spinning gives better odds

Hints

  • Calculate probabilities for both options

  • Consider the current state of the revolver

Solution (Click to reveal)

Spinning gives 1/6 = 16.67% chance of death. Not spinning gives 1/5 = 20% chance. Always spin.

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