Сложение:
7/10 + 9 + 2/15 = 9 + 7/10 + 2/15 = 9 + 21/30 + 4/30 = 9 + 25/30 = 9 5/6
1 7/12 + 3 + 5/9 = 1 + 7/12 + 27/9 = 1 + 7/12 + 30/12 = 1 + 37/12 = 3 1/12
3 1/12 + 4 + 2/15 = 3 + 1/12 + 4 + 2/15 = 3 + 5/60 + 4 + 8/60 = 3 + 13/60 + 4 = 7 + 13/60 = 7 13/60
Итак, 9 5/6 + 3 1/12 + 7 13/60 = 19 11/20.
Сложение:
7/10 + 9 + 2/15 = 9 + 7/10 + 2/15 = 9 + 21/30 + 4/30 = 9 + 25/30 = 9 5/6
1 7/12 + 3 + 5/9 = 1 + 7/12 + 27/9 = 1 + 7/12 + 30/12 = 1 + 37/12 = 3 1/12
3 1/12 + 4 + 2/15 = 3 + 1/12 + 4 + 2/15 = 3 + 5/60 + 4 + 8/60 = 3 + 13/60 + 4 = 7 + 13/60 = 7 13/60
Итак, 9 5/6 + 3 1/12 + 7 13/60 = 19 11/20.