11/15-3/5, 3/20+7/15, 2/9+5/12, 13/16-7/12, 9/14-5/21

Пошаговое объяснение:

11/15-3/5 = 11/15 - 9/15 = 2/15

3/20+7/15 = 9/60 + 28/60 = 37/60

2/9+5/12 = 8/36 + 15/36 = 23/36

13/16-7/12 = 39/48 - 28/48 = 11/48

9/14-5/21 = 54/84 - 20/84 = 34/84 = 17/42

1)11/15-3/5=11/15-9/15 =2/15

2)3/20+7/15=9/60+28/60=37/60

3)2/9+5/12=8/36+15/36=23/36

4)13/16-7/12=39/48-28/48=11/48

5)9/14-5/21=27/42-10/42=17/42

Пошаговое объяснение: