Correction :

42 : 6 = 7	22 - 1 = 21
12 + 22 = 34	17 - 0 = 17
41 - 17 = 24	18 + 10 = 28
24 - 10 = 14	23 - 7 = 16
5 + 21 = 26	20 - 1 = 19
20 - 17 = 3	27 - 22 = 5
11 : 11 = 1	23 + 17 = 40
4 × 2 = 8	21 + 20 = 41
21 - 15 = 6	32 - 24 = 8
21 + 5 = 26	39 - 15 = 24