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Weakest gunman's best opening move in a truel

Question

Three people fight a duel-to-the-last: you hit with probability 10%10\%, the second shooter with 30%30\% and the third with 60%60\%. Shots are taken one at a time in the order you, then the 30%30\% shooter, then the 60%60\% shooter, cycling until one person remains. The others always aim at the most accurate opponent still standing. At whom should you aim your first shot?

Short answer

Nobody: deliberately miss (fire into the air). If you kill the 60%60\% shooter you face the 30%30\% shooter, who fires first at you; killing the 30%30\% shooter is worse still. By wasting your shot the two stronger players aim at each other, and you get the first shot in whichever duel follows. Working through the states gives a win chance of about 0.2040.204 for missing on purpose versus 0.2020.202 for aiming at the best shooter and 0.180.18 for aiming at the 30%30\% shooter.

Adapted from Crack, Heard on the Street, Q4.16, p.40; question and answer rewritten by SelfMadeQuant.com.

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