Correction :

8 - 0 = 8	24 + 13 = 37
20 + 11 = 31	1 + 11 = 12
22 + 15 = 37	37 - 19 = 18
15 - 2 = 13	9 + 19 = 28
1 × 4 = 4	34 - 22 = 12
31 - 11 = 20	21 + 13 = 34
2 + 16 = 18	20 - 15 = 5
20 + 23 = 43	7 + 20 = 27
0 + 10 = 10	7 + 7 = 14
5 + 1 = 6	1 - 1 = 0