Ответ:

Пошаговое объяснение:

13/25 + 2/25 + 3/25 =

(13+2+3)/25 = 18/25

19/34 - 6/36 + 3/34 =

19/34 - 1/6 + 3/34 =

57/102 - 17/102 + 9/102 =

(57-17+9)/102 = 49/102

7/90 + 55/90 + 1/90 =

(7+55+1)/90 = 63/90 = 7/10

23/40 + 5/40 + 1/40 =

(23+5+1)/40 = 29/40

63/80 + 15/80 - 9/80 =

(63+15-9)/80 = 69/80

20/145 + 18/145 + 29/145 = (20+18+29)/145 = 67/145