Найдите значение выражения (4/15-3/10): 1 3/40+(-2 4/19)*(1/3+4/7)

       1          3          5               4       2
(4/15 - 3/10) : 1 3/40 + (- 2 4/19) * (1/3 + 4/7) = - 2 4/129
1) 4/15 - 3/10 = 8/30 - 9/30 = - 1/30
2) 1/3 + 4/7 = 7/21 + 12/21 = 19/21
3) - 1/30 : 1 3/40 = - 1/30 : 43/40 = - 1/30 * 40/43 = - 1/3 * 4/43 = - 4/129
4) - 2 4/19 * 19/21 = - 42/19 * 19/21 = - 2
5) - 4/129 + (-2) = - 4/129 + (- 258/129) = - 262/129 =  - 2 4/129