Помогите с 640, пожалуйста

1) 3*(-4) / 8 + 5 = -12/8 + 5 = -1,5 + 5 = 3,5 2) -5/9 * 3/1 - 7 = -5/3 * 1 - 7 = - 5/3 - 7 = - 5/3 - 21/3 = -26/3 = - 8 (целых) 2/3 3) - 6/5 - 4/5 = - 10/5 = -2 4) 5/12 : 1/4 + 1/3 = 5/12 * 4/1 + 1/3 = 5/3 * 1 + 1/3 = 5/3 + 1/3 = 6/3 = 2 5) -4/2 - 5 = -2 - 5 = -7 6) -4/9 * 3/2 + 1 = -2/3 + 1 = - 2/3 + 3/3 = 1/3 Вот.