Пошаговое объяснение:
9 11/5 - 4 = 9 + 11/15 - 4 = (9 - 4) + 11/15 = 5 + 11/15 = 5 11/15,
8 3/17 - 4 11/17 = (7 + 1 3/17) - 4 11/17 = 7 20/17 - 4 11/17 = 3 9/17,
10 15/16 - 3 15/16 = (10 - 3) + (15/16 - 15/16) = 7 + 0 = 7,
7 15/19 + 4 1/12 = (7 + 4) + (15/19 + 1/12) = 11 + (180/228 + 19/228) =
= 11 + 199/228 = 11 199/228