An urn contains 4 white and 3 red balls. Let X be the number of red balls in a random draw of 3 balls. Find the mean and variance of X.

Explanation

To solve the problem of finding the mean and variance of the random variable \( X \), which represents the number of red balls drawn from an urn containing 4 white and 3 red balls when drawing 3 balls, we will follow these steps:

### Step 1: Identify the Possible Values of \( X \)
The possible values for \( X \) (the number of red balls drawn) can be:
- \( X = 0 \) (no red balls)
- \( X = 1 \) (one red ball)
- \( X = 2 \) (two red balls)
- \( X = 3 \) (three red balls)
...