(3\4 - 5\6) * 3 + (3\4 + 5\6) * 4
(3\4 - 5\6) * 3 + (3\4 + 5\6) * 4 = 2,3
(3\4 - 5\6) * 3 + (3\4 + 5\6) * 4 = 6 1/12 3\4 - 5\6 = 18/24 - 20/24 = - 2/24 = -1/12 -1/12*3= -3/12= - 1/4 3\4+5\6 = 38/24 = 19/12 19/12*4= 19/3 -1/4 + 19/3 = -3/12 + 76/12 = 73/12 = 6 1/12