Latex symbol average

Latex how to write symbol average: \overline

Latex how to write symbol average: \overline

$\overline{X}$

$$\bar{X}$$

Examples

$$\overline{X}$$

$$\overline{X_n}$$

$$\overline{XY}$$

$$\overline{x}=\frac{1}{n} \sum_{i=1}^{n} x_{i}=\frac{1}{n}\left(x_{1}+\cdots+x_{n}\right)$$

$$\bar{X}$$ $$\overline{X_n}$$ $$\overline{XY}$$ $$\bar{x}=\frac{1}{n}\sum _{i=1}^n{x}_i=\frac{1}{n}(x_1+\cdots +x_n)$$