Correction :

42 : 7 = 6	72 : 9 = 8
29 - 11 = 18	28 : 4 = 7
25 - 6 = 19	21 - 0 = 21
10 + 3 = 13	5 + 17 = 22
6 + 18 = 24	1 × 8 = 8
16 + 3 = 19	41 - 20 = 21
33 - 23 = 10	24 + 19 = 43
17 - 6 = 11	34 - 16 = 18
26 - 9 = 17	22 + 20 = 42
3 × 2 = 6	8 + 9 = 17