The Fair Coin Toss Riddle

Difficulty	Categories	Source	I know the solution
🌶️🌶️ Medium	probability, algorithms	I forget	Yes

You have a weighted coin. The coin lands on heads more often than tails, but you don’t know exactly the proportion of heads to tails. You plan to make an important decision using this coin, and want to make sure that either choice will happen with exactly 50% probability. What system can you use that generates a 50% probability using the weighted coin?

Daniel’s Notes

The solution must be precise - you can’t use sampling to estimate the ratio of heads to tails.