426. а) 5/5 - 2/5 = 3/5 б) 4/4-3/4 = 1/4 в) 7/7-4/7 = 3/7 г) 11/11-10/11 = 1/11 427. а) 16/16-1/16-3/16 = 15/16-3/16 = 12/16 = 3/4 б) 25/25-2/25-8/25 = 23/25-8/25 = 15/25 = 3/5 в) 24/24-7/24-5/24 = 17/24-5/24 = 12/24 = 1/2 г) 30/30-17/30-11/30 = 13/30-11/30 = 2/30 = 1/15