Пошаговое объяснение:
42 - 9/14 = 41 14/14 - 9/14 = 41 + (14/14-9/14) = 41 5/14
27 - 7/15 = 26 15/15 - 7/15 = 26 + (15/15-7/15) = 26 8/15
35 - 13/19 = 34 19/19 - 13/19 = 34 + (19/19 - 13/19) = 34 6/19
