7 3/5 + 11 4/9 =

5 2/5 - 2 7/10

3 answers

18 8/45

7 3/5 + 11 4/9 = 38/5 + 103/9 = (38*9)/45 + (103*5)/45
= 342/45 + 515/45
= 857/45
= 855/45 + 2/45 = 19 2/45

or
18 + 3/5 + 4/9 = 18 + 27/45 + 20/45 = 18+47/45 = 19 2/45