а) 3/7 + 5/14 = (6+5)/14 = 11/14
б) 8/9 - 7/12 = (32-21)/36= 11/36
в) 11/50 - 3/25 + 1/20 = (22-12+5)/100 = 15/100 = 3/20
а) 3/7 + 5/14 = (6+5)/14 = 11/14
б) 8/9 - 7/12 = (32-21)/36= 11/36
в) 11/50 - 3/25 + 1/20 = (22-12+5)/100 = 15/100 = 3/20