A release-checked easy problem for training Probability.
Question
You roll two fair dice. If you get double $6$s, you receive $\$100$. If you get a $6$ and a non-$6$, you lose $\$x$. If you get anything else, you reroll both dice until you get double $6$s or a $6$ and non-$6$. What is the maximum value of $x$ where the game still has non-negative expected value?
Practice focus
This Probability problem is tagged Probability. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.