17/20 + 0.7 = 17/20 + 14/20 = 31/20
17/20 - 0.7 = 17/20 - 14/20 = 3/20
13/25 + 0.37 = 13/25 + 37/100 = 63/100
13/25 - 0.37 = 13/25 - 37/100 = 3/100
0.13 + 4/5 = 0.13 + 0.8 = 0.93
0.13 - 4/5 = 0.13 - 0.8 = -0.67
17/20 + 0.7 = 17/20 + 14/20 = 31/20
17/20 - 0.7 = 17/20 - 14/20 = 3/20
13/25 + 0.37 = 13/25 + 37/100 = 63/100
13/25 - 0.37 = 13/25 - 37/100 = 3/100
0.13 + 4/5 = 0.13 + 0.8 = 0.93
0.13 - 4/5 = 0.13 - 0.8 = -0.67