Question

1) The variance of 3,4,5 is​

Answer 1

$mean = \frac{3 + 4 + 5}{3} \\ \\ mean = \frac{12}{3} \\ \\ mean = 4$

(x1 - mean)² = (3 - 4)² = (-1)² = 1

(x2 - mean)² = (4 - 4)² = (0)² = 0

(x3 - mean)²= (5 - 4)² = (1)² = 1

$variance = \frac{ sum \: of({xi - mean})^{2} }{n} \\ \\ variance = \frac{1 + 0 + 1}{3} \\ \\ variance = \frac{2}{3} \\ \\ variance = 0.66$