Jane Street–styleTraderAssistant TraderQuestion #196
Person A has a 30-sided die and person B has a 20-sided die. Both players roll, and the person with the highest roll wins (on a draw, B wins). The loser pays the winner the value shown on the winner's die. 1. Calculate the expected value of this game for player A. 2. How does this value change if player B can re-roll, and when should B re-roll? 3. Now, how much is it worth for player A to get a re-roll option in this scenario? 4. If player A cannot re-roll, how many re-rolls would player B need in order to be favored in the game?
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