MediumMarket Making & Games
The Doubling “System”
SIG / SusquehannaFive Rings
On a fair even-money coin flip you play the classic martingale: bet $1, and after every loss double the stake until the first win, then stop. Ignoring any table or bankroll limit, how many dollars does every completed run of this system win?
Approach
Add up the losses just before the first win.
Then ask what happens to the stake sizes along the way.
Answer
Show the final answer
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