The values of discrete r.v. are generally obtained by ....................

Answer

To solve the question "The values of discrete r.v. are generally obtained by ....................", we need to understand what a discrete random variable (r.v.) is and how its values are determined.

### Step-by-Step Solution:

1. **Understanding Discrete Random Variable**:
- A discrete random variable is defined as a variable whose values are obtained by counting. This means that the possible values of a discrete random variable are distinct and separate, often represented by whole numbers.

2. **Examples of Discrete Random Variables**:
- To illustrate this concept, we can consider some examples:
- **Number of Students in a Class**: The number of students can be 1, 2, 3, etc., but cannot be a fraction like 1.5.
- **Number of Heads in Coin Flips**: When flipping a coin multiple times, the number of heads can only be a whole number (0, 1, 2, etc.).

3. **Conclusion**:
- Based on the definition and examples, we can fill in the blank in the question. The values of discrete random variables are generally obtained by **counting**.

### Final Answer:
The values of discrete r.v. are generally obtained by **counting**.

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