9/10
8/10 + 4/5 = 8/5 or 13/5
3/5 + 2/4 = 6/10 + 5/10 = 11/10
1/5 + 4/10 = 1/5 + 2/5 = 3/5
4/10 + 1/5 = 2/5 + 1/5 = 3/5
4/10 or 2/5
2
It is: 11/10 or 1 and 1/10
It is: 1/2+4/5 = 13/10 or as 1 and 3/10
10 1/4
9/10 + 4/5 = 9/10 + 8/10 = 17/10 = 1 7/10
2/5 + 3/10 = 4/10 + 3/10 = 7/10