Вычислите: (-7)-(-3.6):(1.2)(6 3/7):(-9)+4 1/3(-7/24)*(1 1/7)*3(-2.7):(-1 4/5)*(1 5/9)Всё в квадратных скобках!

а) [( - 7) - ( - 3,6) / (1,2)] = 7 - 3,6 / 1,2 = 7 - 3 = 4.
б) [(6 3/7) / ( - 9) + 4 1/3] = 6 3/7 / 9 + 4 1/3 = (45 * 7)/(7 * 63) + 13/3 = 315/441 + 13/3 = 5/7 + 13/3 = (15 + 91)/21 = 106/21 = 5 1/21.
    6 3/7 = (6 * 7 + 3)/7 = 45/7.
    4 1/3 = (4 * 3 + 1)/3 = 13/3.
    9 = 8 7/7 = (8 * 7 + 7)/7 = 63/7.
    315/441 сократим на 63 = 5/7.
в) [( - 7/24) * (1 1/7) * 3] = 7/24 * 1 1/7 * 3 = 1.
    1 1/7 = (1 * 7 + 1)/7 = 8/7.
 1. 7/24 * 8/7 = (7 * 8)/(24 * 7) = 56/168 = 1/3.
 2. 1/3 * 3 = 1.
г) [( - 2,7) / ( - 1 4/5) * (1 5/9)] = 2,7 / 1 4/5 * 1 5/9 = 2 1/3.
    2,7 = 2 7/10 = (2 * 10 + 7)/10 = 27/10.
    1 4/5 = (1 * 5 + 4)/5 = 9/5.
    1 5/9 = (1 * 9 + 5)/9 = 14/9.
 1. 27/10 / 9/5 = (27 * 5)/(10 * 9) = 135/90 на 45 = 3/2.
 2. 3/2 * 14/9 = (3 * 14)/(2 * 9) = 42/18 сократим на 6 = 7/3 = 2 1/3.