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Seeker's first spot turning up empty

Question

Two players each choose one of five hiding places independently and uniformly at random (they may pick the same one). A seeker then searches one of the five places, also chosen uniformly at random. What is the probability that nobody is hiding in the place the seeker checks first?

Short answer

16/2516/25. Whatever spot the seeker picks, each hider independently avoids it with probability 45\tfrac45, so the spot is empty with probability (45)2=1625\left(\tfrac45\right)^2=\tfrac{16}{25}.

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

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