1) 1/9 + 2,75 + 1/5 = 1/9 + 2 3/4 + 1/5 = 20/180 + 2 135/180 + 36/180 = 2 191/180 = 3 11/180
2) 2,5 +5 1/7 - 2 3/14 = 2 1/2 + 5 1/7 - 2 3/14 = 2 7/14 + 5 2/14 - 2 3/14 = 5 6/14 = 5 3/7
3) 8,5 + 5/6 - 6,25 = 8 1/2 + 5/6 - 6 1/4 = 8 6/12 + 10/12 - 6 3/12 = 12 13/12 = 13 1/12
4) 7,6 - 4 2/3 + 2 1/15 = 7 3/5 - 4 2/3 + 2 1/15 = 7 9/15 - 4 10/15 + 2 1/15 = 5
5) 2,25 + 11 1/15 - 7 1/6 = 2 1/4 + 11 1/15 - 7 1/6 = 2 15/60 +11 4/60 - 7 10/60 = 6 9/60 = 6 3/20
6) 6,8 -2 1/3 +1,2 = 6 4/5 -2 1/3 + 1 1/5 = 6 12/15 -2 5/15 + 1 3/15 = 5 10/15 = 5 2/3