Question

Статистика.Полигон частот не стройте ток..)

Answer 1

Ответ:

Пошаговое объяснение:

$M(x)= \sum_i x_i p_i = 9 * 0.2 + 5 * 0.2 + 6 * 0.1 + 1 * 0.2 + 3 * 0.3 = 1.8 + 1 + 0.6 + 0.2 + 0.9 =\\= 4.5\\D(x)=\sum_i p_i (x_i - M(x))^2=0.2 * (9 - 4.5)^2 + 0.2 * (5-4.5)^2 + 0.1 * (6 - 4.5)^2 +\\+ 0.2 * (1 - 4.5)^2 + 0.3 * (3 - 4.5)^2 = 0.2 * (4.5^2 + 0.5^2 + 3.5^2) + (0.1 + 0.3) * 1.5^2 =\\= 0.2 * 0.25 * 131 + 0.4 * 0.25 * 9 = 0.2 * 0.25 * 149 = 7.45\\\sigma_x = \sqrt{D(x)}= \sqrt{7.45}$