Ответ:
Пошаговое объяснение:
5 3/4 = 23/4
11/7 = 1 4/7
6 1/2 = 13/2
23/9 = 2 5/9
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1/3 + 5/21 = (7+5)/21 = 12/21 = 4/7
4/5 - 3/7 = (28-15)/35 = 13/35
1 - 5/7 = 7/7 - 5/7 = 2/7
3/5 : 9/5 = 3/5 * 5/9 = 1/3
8 : 1/9 = 8 * 9 = 72
1/3 * 42 = 1 * 14 = 14
12 - 3 3/7 = 11 7/7 - 3 3/7 = 8 4/7