Correction :

8 + 19 = 27	20 + 5 = 25
110 : 11 = 10	0 + 0 = 0
19 - 8 = 11	7 - 1 = 6
10 + 5 = 15	4 × 8 = 32
7 - 3 = 4	1 × 3 = 3
23 + 22 = 45	29 - 17 = 12
90 : 9 = 10	0 + 15 = 15
17 - 11 = 6	54 : 9 = 6
5 - 2 = 3	23 - 23 = 0
6 : 2 = 3	21 + 19 = 40