Correction :

6 + 20 = 26	25 - 9 = 16
5 × 5 = 25	3 + 22 = 25
8 - 4 = 4	11 + 11 = 22
26 - 7 = 19	19 + 16 = 35
33 - 20 = 13	11 - 9 = 2
1 + 4 = 5	14 - 4 = 10
23 + 12 = 35	11 + 23 = 34
36 : 4 = 9	21 + 0 = 21
7 + 11 = 18	8 + 19 = 27
31 - 14 = 17	12 + 0 = 12