а) 3 5/16 + 1/4 - 2 1/16  = 3 5/16 + 4/16 - 2 1/16 = 3 9/16 - 2 1/16 = 1 8/16 = 1 1/2

в) 6 11/12 - 3 1/6 - 1 1/4 = 6 11/12 - 3 2/12 - 1 3/12 = 3 9/12 - 1 3/12 = 2 6/12 = 2 3/6 = 2 1/2

б) 1/8 + 2 3/5 + 2 7/8 = 5/40 + 2 24/40 + 2 35/40 = 2 29/40 +  2 35/40 = 5 24/40 = 5 6/10 = 5 3/5

г) 3 7/9 - 1 5/18 + 3 1/2 = 3 14/18 - 1 5/18 + 3 9/18 = 2 9/18 + 3 9/18 = 6