Question

Let \( X \) denote the sum of the numbers obtained when two fair dice are rolled. The variance and standard deviation of \( X \) are?

• A. \( \frac{31}{6} \)
• B. \( \frac{35}{6} \)
• C. \( \frac{17}{6} \)
• D. \( \frac{31}{7} \)

Hint:

The variance and standard deviation of the sum of independent random variables is the sum of their individual variances.

Answer 1

The Correct Option is B

The variance of a sum of two dice rolls can be calculated by first determining the mean and then using the formula for the variance of the sum of independent random variables.