6 4/5 + 3 2/4 =
11 3/5 + 9 1/4 =
1 1/5 - 2 2/5 =
8 3/6 - 2 2/6 =
7 1/8 - 2 3/4 =
1 3/4 - 2/3 =
18 1/5 - 2 2/4 =​