Make chance fair
Heads and tails need not be equally likely. Find a procedure that gives every output the same chance.
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Whole procedures · Balance each group of equally likely sequences.
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6 questions · No time limit
Example
Example
Example · Standard
Which procedure makes the 2 outputs equally likely for every allowed coin bias?
Coin X has an unknown, fixed chance of heads. Every flip is independent. Each chance is strictly between 0 and 1.
| Procedure | Output 1 | Output 2 |
|---|---|---|
| A | TTH HTT | HTH HHT |
| B | HTH HHT | TTH HTT |
| C | TTH HTH | HTT HHT |
Any unlisted sequence means: discard the whole block and try again with fresh flips. Repeat the same procedure until it gives an output.
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Choose the procedure that makes all outputs equally likely for every allowed coin bias.
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Each coin has an unknown, fixed chance of heads strictly between zero and one. Every flip is independent. Read each block in order. A listed sequence gives its assigned output; otherwise discard the block and repeat the same procedure with fresh flips. Find a guarantee that holds for every allowed bias, not just a fair coin. Two named coins may have different biases.
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About this practice
Learn a method
Check equal outcome chancesHeads and tails need not be equally likely. Find a procedure that gives every output the same chance.
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Optional and off by default. Share starts, completions, replays and error categories. For visits from ChatGPT, starts and completions can also include the first QuickenBrain page and broad country. No answers, drawings or names.
How this data is used