1/10 + 7/20 - 2/40 = 2/20 + 7/20 - 1/20 = 8/20 = 2/5
17/20 - 3/10 - 11/60 = 51/60 - 18/60 - 22/60 = 51/60 - 40/60 = 11/60
3/20 + 7/10 - 3/40 = 6/40 + 28/40 - 3/40 = 31/40
9/40 + 3/4 - 19 = 9/40 + 30/40 - 760/40 = -721/40
1/10 + 7/20 - 2/40 = 2/20 + 7/20 - 1/20 = 8/20 = 2/5
17/20 - 3/10 - 11/60 = 51/60 - 18/60 - 22/60 = 51/60 - 40/60 = 11/60
3/20 + 7/10 - 3/40 = 6/40 + 28/40 - 3/40 = 31/40
9/40 + 3/4 - 19 = 9/40 + 30/40 - 760/40 = -721/40