Ответ:

1. 3/5+4/7=21+20/35=41/35

2. 1/4+7/9=9+28/36=37+36

3. 1/2+3/4=2+3/4=5/4

4. 13/15+9/10=26+27/30=53/30

Ответ:

3/5 + 4/7 = 21/35 + 20/35 = 41/35 = 1 6/35

1/4 + 7/9 = 9/36 + 28/36 = 37/36 = 1 1/36

1/2 + 3/4 = 2/4 + 3/4 = 5/4 = 1 1/4

13/15 + 9/10 = 26/30 + 27/30 = 53/30 = 1 23/30

Пошаговое объяснение: