1: 1/5 + 3.4 = 3.6
2: 0.875 - 3/20 = 0.725
3: 0.1 - ( -31/50) = 0.72
4: 0.3 - 5/24 = 0.09 (5/24 = 0.2083333... So, it has been rounded to 0.21)
5: -5/6 x -0.9 = 0.72 (-5/6 = -0.833333.... It has been rounded to -0.8)
6: 1 3/4 / 2 = 0.875
I hope this helps. :)
