medium   Probability

Sum Over Min Die

A release-checked medium problem for training Events, Discrete Random Variables, Expected Value.

Question

You have been tasked to find the expected value of a die game in which you are rolling $2$ dice at a time. Your first roll of the dice will all be summed up and will be your starting score. Your next, and final, roll of the $2$ dice will be your divisor, in which you are going to pick the optimal die out of the two to divide your total by, which will be your final score. $$ $$ Calculate the expected value of playing this game optimally.

Practice focus

This Probability problem is tagged Events, Discrete Random Variables, Expected Value. State the random variables and conditioning information explicitly, then check the result against boundary cases before opening hints or a solution.

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