# The variance of first 50 even natural numbers is

## Solution :

$${\sigma^2}$$ = $$\sum(x_i – \bar{x})^2\over n$$

$$\bar{X}$$ = $$\sum x_i\over n$$

= $$2 + 4 + 6 + 8 + ….. + 100\over 50$$

= 51

$${\sigma^2}$$ = $$2^2 + 4^2 + …. + 100^2\over 50$$ – $$51^2$$

= 833

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