(1/3 - 5/16) : (1/6 - 1/8) = (16-15)/16 : (3-4)/24 = 1/16 : (-1/24) = 1/16 * (-24/1) = -3/2 = - 1 1/2
(5/7 - 2/3) : (3/9 - 5/12) = (15-14)/21 : (12-15)/36 = 1/21 : (-3/36) = 1/21 * (-36/3) = -12/21
(3 1/8 + 1 3/4) х = 2 1/6
(25/8+7/4)х = 13/6
(25+14)/8х = 13/6
63/8х = 13/6
х = 13/6 : 63/8 = 13/6 * 8/63 = 13/3 * 4/63 = 52/189
(2 1/12 - 1 5/6) х= 2 1/6
(25/12 - 11/6)х = 13/6
(25-22)/12х = 13/6
3/12х = 13/6
х = 13/6 : 3/12 = 13/6 * 12/3 = 13/1 * 2/3 = 26/3 = 8 2/3