The variance (var) of a constant value, such as 3, is 0. Here’s why:

Explanation:

Variance measures the spread of a set of numbers from their mean (average). However, if all numbers in the dataset are the same (like 3, 3, 3, ...), the mean is also 3, and all individual deviations from the mean are 0. Thus, the variance becomes:

$\text{Var}(3) = \frac{1}{n} \sum_{i=1}^{n} (3 - 3)^2 = 0$

Final Answer:

$\boxed{0}$

Would you like to explore more about variance or its applications?

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5 Related Questions:

1. What is the variance of a general dataset?
2. How is the standard deviation related to variance?
3. What is the variance of a linear transformation of a constant?
4. What happens to the variance when you scale or shift data?
5. How does variance behave with multiple random variables?

Tip: When the dataset has no variability, its variance will always be zero!