Modeling5

import random

a_m = 25
a_sig = 5
b_m = 30
b_sig = 3
n = 1000


def get_random(m, sig):
    sum_ = 0
    for _ in range(0, 12):
        sum_ += random.uniform(0, 1)
    return m + sig * (sum_ - 6)


def get_random_c():
    x = random.uniform(0, 1)
    if x < 0.1:
        return 10
    elif x < 0.35:
        return 20
    elif x < 0.85:
        return 30
    else:
        return 40


res = []
for _ in range(0, n):
    a = get_random(a_m, a_sig)
    b = get_random(b_m, b_sig)
    c = get_random_c()
    res.append((a + b) / c)

M = float(sum(res)) / max(len(res), 1)
D = 0
for el in res:
    D += pow(el - M, 2)

D /= n - 1


print("Мат ожидание: {}".format(M))
print("Дисперсия: {}".format(D))