a) 5/9 + 3/9 = 8/9
b) 5/7 + 3/7 = 8/7 = 1 1/7
c) 2 4/9 + 2/9 = 2 6/9 = 2 2/3
d) 3 5/7 + 2 6/7 = 5 11/7 = 6 4/7
e) 12/13 - 7/13 = 5/13
f) 5 16/23 - 2 7/23 = 3 9/23
g) 8 - 4/7 = 7 3/7
h) 5 1/6 - 1 5/6 = 3 1/6 + 1/6 = 3 2/6 = 3 1/3
h) 5 1/6 - 1 5/6 = 4 7/6 - 1 5/6 = 3 2/6 = 3 1/3
:)