4 5/9+2 8/9
5 1/13-3 6/13
7 2/15-(4-3 7/15)+2 12/15

4 5/9 + 2 8/9 = 41/9 + 26/9 = 67/9 = 7 4/95 1/13 - 3 6/13 = 66/13 - 45/13 = 21/13 = 1 8/137 2/15 - (4 - 3 7/15) + 2 12/15 = 107/15 - (60/15 -52/15) + 42/15 = 131/15 = 8 11/15