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Probability puzzles require you to weigh all the possibilities and pick the most likely outcome.


Puzzle ID:#31704
Fun:*** (2.54)
Difficulty:*** (2.31)
Submitted By:Cogmatic*de****
Corrected By:Winner4600




One day, two friends named Al and Bob found a shiny quarter on the ground. To decide who would get it, Al would flip the coin. If it came up heads, then Al would keep it, but if it was tails, Bob would have to flip for it. If Bob got heads, Bob would keep the coin, but if he got tails, then Al would flip it and the entire process would repeat. Assuming that Al goes first and that the coin has an equal chance of landing on either heads or tail, what is the probability that Al would keep the coin?

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