Expected Value of a Dice Roll

Computing expected value of a fair die roll in Python

This is a fundamental probability coding problem that tests whether you can translate the mathematical definition of expected value into clean, working code. Expected value calculations are core to quantitative finance—traders at firms like IMC use them constantly to evaluate the worth of bets, positions, and market opportunities.

The problem asks you to compute the average outcome of rolling a fair n-sided die. The key is recognizing that expected value is a weighted sum: each outcome (die face) contributes to the total in proportion to its probability. For a fair die, all probabilities are equal, which simplifies the calculation. Your solution should be correct, readable, and handle edge cases like a single-sided die.

• Linearity of expectation and probability weighting
• Recognizing closed-form solutions vs. iterative computation
• Precision and rounding in numerical output