Correction :

17 - 15 = 2	25 - 5 = 20
13 - 8 = 5	25 - 9 = 16
25 : 5 = 5	33 - 24 = 9
33 - 19 = 14	21 + 0 = 21
81 : 9 = 9	10 + 14 = 24
38 - 22 = 16	2 + 22 = 24
21 - 3 = 18	17 + 0 = 17
5 + 3 = 8	9 + 16 = 25
15 + 10 = 25	16 - 6 = 10
27 - 11 = 16	1 + 22 = 23