Let a pair of dice be thrown and the random variable `X` be the sum of the numbers that appear on the two dice. Find the mean or expectation of `X`.

Explanation

To find the mean or expectation of the random variable \( X \), which represents the sum of the numbers appearing on two thrown dice, we can follow these steps:

### Step 1: Identify the Sample Space
When two dice are thrown, each die has 6 faces. Therefore, the total number of outcomes when throwing two dice is:
\[ 6 \times 6 = 36 \]

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