11\45+10\45
1\3+1\4
1\2-2\9

11/45 + 10/45 = 21/45 = 7/15

1/3 + 1/4 = 4/12 + 3/12 = 7/12

1/2 - 2/9 = 9/18 - 4/18 = 5/18

Пошаговое объяснение:

11/45 - 10/45 = 1/45

1/3 + 1/4 = 4/12 + 3/12 = 7/12

1/2 - 2/9 = 9/18 - 4/18 = 5/18