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Fair Toss (Posted on 2024-07-02)

Suppose you have one fair coin, that is, a coin that comes up heads half the time and tails half the time.

Show how to use this coin to choose fairly among N people. Solutions using the fewest coin tosses are preferred.

No Solution Yet Submitted by K Sengupta

Rating: 5.0000 (1 votes)

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re: current thoughts

| Comment 8 of 12 |

(In reply to current thoughts by Larry)

Excellent! I agree that the best approach we have so far found to N = 9 is to use "inflate and gamble" to select a group of 3, and then use "inflate and gamble" to pick one of those 3.

2 * 4/3 + 2 * 4/3 = 5.333 expected flips

Posted by Steve Herman on 2024-07-02 21:03:19

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