Correction :

18 + 16 = 34	17 + 21 = 38
2 + 2 = 4	6 + 1 = 7
72 : 8 = 9	7 × 9 = 63
17 + 3 = 20	5 + 2 = 7
17 - 9 = 8	10 × 11 = 110
23 - 0 = 23	9 - 1 = 8
7 × 6 = 42	34 - 10 = 24
5 + 2 = 7	44 : 11 = 4
5 × 10 = 50	40 - 16 = 24
10 - 8 = 2	9 + 9 = 18