А = 8.3
b = 10
a-b = 8.3-10 = -1.7
a = -2 1/2
b = -3
a-b = -2 1/2 - (-3) = 1/2 = 0.5
a = 9 1/5
b = -13 3/5
a-b = 9 1/5 - (-13 3/5) = 9 1/5 + 13 1/5 = 22 2/5 = 22.4
a = -4.75
b = 3 1/4
a-b = -4.75 - 3 1/4 = -4.75-3.25 = -8
a = -13.94
b = -20
a-b = -13.94-(-20) = -13.94+20 = 6.06