а) 2 13\30 - (1 1\10+1\5) = 1 2/15
1 1\10+1\5 = 1 1/10 + 2/10 = 1 3/10
2 13/30 - 1 3/10 = 2 13/30 - 1 9/30 = 1 4/30 = 1 2/15
б) 2 8\15-(1 3\10+2\5) = 5/6
1 3\10+2\5 = 1 3/10 + 4/10 = 1 7/10
2 8/15 - 1 7/10 = 2 16/30 - 1 21/30 = 1 46/30 - 1 21/30 = 25/30 = 5/6
в) 4 14\45-1 7\15-3\5 = 4 14/45 - 1 21/45 - 27/45 = 3 59/45 - 1 21/45 - 27/45 = = 2 38/45 - 1 21/45 = 1 17/45
г) 4 11\30-2 9\20-1\10 = 4 22/60 - 2 27/60 - 6/60 = 4 22/60 - 2 21/60 = 2 1/60